Frank Marshall the Legend-3
The last line I am going to talk about which Frank Marshall created is known as:
This line is played with the black pieces.
Rating Scale: 500-2700
The Above Diagram is the Starting Position of the Marshall Attack.
The name of the line white is playing is called the Ruy Lopez (Spanish Game). Due to the difficulty the black sided players had in this line coupled with the fact Ruy Lopez was a priest during the Spanish Inquisition. Black sided players had a nickname for this line which they called "The Spanish Torture" becuase it was a very hard line for black sided player to try and equalize from. The Ruy Lopez is still heavily used till this very day. It is considered a very theoritical opening line. Their are hundreds of different variations played against it today. The one I will be showing you is a line exclusively created by Frank Marshall. Frank Marshall was considered a very aggressive attacking player. Naturally, The line he created is exactly that lol a very aggressive attacking line lol.
The line I will be showing you has gone through some name changes over the last couple of decades. As modern theory/openings have evolved so has some of the names.
I would like to give you a brief history of the name changes if I may. The line was first called the Marshall Attack from my understanding.
Grand Masters when it was first seen and played considered it to be a pure all out attack against the white sided player. I will be showing you pictures and imagines lol so you can see later on and get your opinion on it. As chess players have gotten better and technology has gotten better they have started changing the name of the line. The name they have started calling it is the Marshall Gambit.
In this line you do give up 1 pawn. So if you was to look up the definition of the word Gambit it would meet the criteria. Usually when you do a Gambit you give up material in exchange/compensation for something esle in this case its a better piece development to try and pursuit an aggressive attack.
So if you are wondering why I have it named as Marshall Attack with a slash ( / ) Gambit it is becuase of that reason.
Now I like to think of it as a Attack I don't care if the pawn is lost lol. Frankly I believe that pawn isn't "Gambitted" I believe it is a pawn sacrifice for a mating attack lol. When you go for a mating attack. You don't sacrifice a knight and say you Gambitted the knight lol. You say you did a knight sacrifice. So that is my stance on this issue incase you wanted to know. It is highly debated topic still today. I did add both the titles of Marshall Attack/Gambit just to be precise.
You have the luxury to call it what you like. Marshall Attack or Marshall Gambit? That is a decision you will have to make for yourself. Some databases call it Marshall Attack and others call it Marshall Gambit so yeah. I believe Grand Masters in the past were correct in calling it the Marshall Attack and not the Marshall Gambit.
Than you hear some modern GM's say its just a Gambit HA. If its just a Gambit than why do GM's seek to avoid it? Why did GM's create "Anti-Marshall Systems". If its just a gambit than they should have nothing to fear. Yeah its not a Gambit its an Attack they ruffle my feathers.
Ok Well lets get on with it so you can see for yourself. I believe for you to fully understand the Marshall Attack you have to understand some of the idea's in the Ruy Lopez. So What I plan on doing is to try and show some of the idea's in the Ruy Lopez to help you understand the Marshall Attack better.
I will show you alternative moves which can be played by white and black ;however, I will not go into them very deeply.I just want to show you alternative moves incase you feel like trying out other lines/openings.
OK so lets start at Move 1.
1.e4 and black response with 1...e5. This is what we consider to be Classical chess at its finest. If you are a beginner you can never go wrong opening like this. White plays his pawn in the center. Black responds with the same pawn in the center seeking to establish himself from getting a cramped position.
White plays the move 2.Nf3 the goal of this move is to attack the e5 pawn. If black does nothing white will simply take the e5 pawn and be up 1 pawn. So what black usually does is try to defend his e5 pawn. Two very common ways of doing that is with the moves 2...Nc6 or 2...d6. In higher level chess the best move is considered to be the move 2...Nc6. In very high level chess 2...d6 is not played alot any more becuase it is not considered as great.
However, It does seem very popular in club level chess. The name of the line 2...d6 is called the " Philidor Defence" If you wish to get more information on it you will have to look it up. I am sololy going to cover the moves leading up to the Marshall Attack. However, at least you have the name to get you started in your search if you do want to try that line out.
OK the move 3.Bb5 by white signals the Ruy Lopez. White is playing the Ruy Lopez(Spanish Game) that is the starting position for white.
The idea with the move 3.Bb5 is to try and pressure the knight. As you can see. White tryed to attack the e5 pawn with his knight on f3. Black responded by defending the e5 pawn with his knight on c6. Now white has decided to attack the knight on c6 that is defending the e5 pawn. White's idea would be to try and take the knight and win the e5 pawn. The problem is the idea does not work just yet. I will show you why at move 4.
One of the most popular options for black is to try and attack the bishop with the move a6. He is bascially trying to say take my knight lol. Bascially trying to lure white into giving up his powerful Light Square Bishop for the knight.
Another move which high level players have played in this position quite alot recently is the move Nf6 which is known as the (Berlin Defence) Very strong defence by black as well. If you wish to learn more about that. You will have to find another blog lol. However, at least you have a name to have some reference too. I also listed a few other possible defences that have been played. As you can see the reputation of the Ruy Lopez being theoritical is true look at all those lines lol. I added their names incase you felt like trying them later on in your chess career or mixing it up playing other lines.
After Black plays a6 attacking whites bishop white has 2 options. He can either take the knight or drop the bishop back.
If white takes the knight with his bishop. That is known as the Ruy Lopez, Exchange Variation which is a very popular continuation for white till this very day as well.
If white choses to take the knight on c6 he has to be careful he can not take the e5 pawn with his knight or he might find himself in some hot water. See below picture. You can see how the black queen goes to d4 threating both the knight and the E pawn.
The Ruy Lopez, Exchange Variation is playable just don't take the e5 pawn and be greedy lol.Usually when players play the Ruy Lopez, Exchange Variation they castle play moves like d3 and Nc3 etc.
However, The most popular line is for white to move his bishop to a4 that is the most played move.
After which black usually responds with the move Nf6 getting its king side development going. Trying to make it so he can castle. I listed some other possible lines that can be played instead of Nf6. Again I will not go deeply into any of those just wanted to add them in as extra incase you might want to mix it up and try other things. You never know lol maybe the Marshall isn't for you lol.
The most standard move for white in this position is simply to castle getting king safety. At the present moment it looks like the e4 pawn is hanging. However, in this position white has found a very clever way of defending the e4 pawn in this variation. I will stress very deeply that normally black players will not take the e4 pawn in this specific position becuase of whites response of d4. I did not plan to go that deep in this;however, since it does look like black can win a pawn. I will touch on it a little bit. My goal is to help you understand why white castles as well as see why black sided players don't play some lines which all will lead up to the Marshall Attack starting position.
I showed the moves in the diagram above if black plays 5...Nxe4. It is called the Open Tarrasch Defence. Bascially white trys to blast open the center since the black king is still in the middle of the board as well as trying to win their pawn back they lost. So the move 6.d4 by white trys to get his pawn back if black trys to keep the pawn than. He will come under heavy fire becuase his king is still unsafe. Usually the moves that follow up are shown in the diagram above. I will be showing a picture to demonstrate some of the idea's white has and some of the pressure white has. Usually white does often win from this position. I mean its still will be a very interesting game to play but many higher levels believe white has a slight edge in this position which is why many black players don't like it.
The red arrows show how white has some pressure on blacks d5 pawn. I mean black is defending the d5 pawn pretty well at the moment so its not the end of the world but it is a little annoying for black. Considering its not that great to have pressure on you lol.
The green arrows show some of the general idea's white has in this position. Sometimes the white player will play the move Nd2 trying to trade off blacks knight right away. other times white will play Qe2 with idea of putting a rook on d1 trying to have it facing the black queen. (which is also pretty scary lol).
It is a very complex position I must say. Most times black sided players will not go down this road. You have to realize black is not castled yet and his bishop is still on f8 in blacks way. It would take black at least 2 moves to castle.( First move to move bishop, Second move to castle).
Which is why most black sided players don't play this way. They look for better prospects/position's. I believe the position is still pretty complex though. It is hard to see how white wins 100%. White does score better in this specific position according to chess databases. They also have some very nice idea's/plan's. I believe that is the main reason why black sided players try for other favorable positions instead of this one.
Moving on to the black responses. Black has multiple responses in this position. For the sole purpose of this blog, I will only comment on the 5...Be7 line for black.
This move bascially allows black the chance to be able to castle. It also develops the bishop to a good spot. It is a powerful defender/attacker on e7 making it very versatile.By playing the bishop to e7 it stops any white bishop pins on the knight. If white has any funny idea's of playing Bg5 trying to pin the knight to the queen the bishop on e7 acts as important rule of breaking the pin.
In some lines after black castles they can move their rook off of the f8 square and drop the bishop on e7 to f8 incase they need extra defence. It can also act as a attacking piece. Some ways black uses it as a attacking piece is they can try and rerout the bishop to g7 moves like Bf8, g6, Bg7 attacking the center pawns. Other possible ways for it to be activated is on f6 or g5. So it has important function's that is for sure.
Also another important factor is it helps in achieving the Starting position of the Marshall Attack if you can rememeber what the starting position looks like that I posted in the beginning of this blog this move also helps in the sequence to reach that position. So again this 5...Be7 move is very multi-purpose.
While we are on this intermission lets look at a cool line that is one of my favorite's. It is actually a pretty reasonable line. It has a very cool name lol. I will not go very in depth with this line becuase it does not achieve the Marshall Attack starting position. I just plan on showing you it briefly becuase I like it. HA HA yeah I'm biased a little bit showing you a line I like. Well its ok It will not take long lol. The important thing is we are learning why each move is played and also learning other moves that have been played so incase we get bored of playing the same line. We can mix it up lol.
The line I will show briefly:
Starts with following move's 5...b5 6.Bb3 Bb7 it is called:
Arch Angel Variation (Defence)
I will admit I do love fianchetto lines and it has a very cool name. People ask you what you play you can say " I play the Arch Angel Variation. It is Heavenly Ha Ha. The bishop gets fianchetteo'ed on b7 and it is a Holy Terror Ha Ha."
Ok no more joking lol lets move on we almost at the Marshall Attack.
Ok at move 6 things start to get real. Major issues start to pop up on both sides the position. The position starts to get really intense.
So lets spend some time here. First let me tell you how many issues their are in this position. Their are 2 main issues. One issue is on the white side and One issue is on the black side. So this can be a turning point lady's and gentlemen. I frequently get asked by players on how to take advantage of mistakes their opponents make. Well here is how you can take advantage of a mistake which can be made in this position. White and Black must play accurate in this position. I would even say they are forced into playing accurate.
Issues in the position:
White - The issue white has in this position at move 6 is the E4 pawn needs to be guarded. If you rememeber on move 5 white didn't have to defend his pawn becuase the black king was still in the middle of the board and it would take black 2 moves to castle(blacks bishop was in the way at the time on f8). In this position it will only take black 1 move to castle(black bishop is on e7 now out of the way). White is forced to play a move that defends his e4 pawn. He has alot of possible moves to defend the e4 pawn with. I gave a list of several different options and variations white can play to defend his E4 pawn. Every single move on the list white plays in this position has to be to defend the e4 pawn in some way. If white does not play a move to defend the e4 pawn. Black will be able to take the e4 pawn.
Notice how every single move in the below picture defends the e4 pawn in some way.Even the move Bxc6 which is a forcing move even it defends the e4 pawn for a short moment. After black recaptures than white can play another move that defends the e4 pawn.
Black- The issue black has in this position at move 6 is the E5 pawn needs to be protected. If you rememeber on move 3 white tryed to pressure the knight on c6 so he can take the knight on c6 than take the e5 pawn. At the time that tactical shot by white did not work becuase black had the chance to play Qd4 hitting the unprotected knight and unprotected e4 pawn. However, in this position if white defends his e4 pawn the threat is now serious. If black does not defend the e5 pawn or break the threat. White will be able to take the e5 pawn
Notice how every single move in the below picture defends the e5 pawn in some way. The move d6 defends the e5 pawn directly. The move b5 breaks the connection of the bishop taking the knight on c6. Basially b5 forces the bishop to retreat so it does not attack the c6 knight any more that is defending the e5 pawn.
Concrete Threat's in this position Lady's and Gentlemen this is a game changer. The loss of a center pawn can not be tolerated. Their will be no compensation for this loss. You might as well resign from this position if you lose your center pawn. You have to rememeber this and if you play against an opponent who does not realize these issues they will lose their center pawn those poor unfortunate souls.
I will show the continuation's that can happen if either side does not play accurately.
Whites point of view in this position: Lets say white defends his e4 pawn successfully and lets pretend black does not see any problem and plays a bad move.
In the above picture white has just played the move 6.Re1. The move 6.Re1 is a move that does successfully defend the e4 pawn. The main function of this move is again to defend the e4 pawn. However, their is also another reason why this move is favored over other responses. For example if you rememeber the diagram I showed white has several moves he could play here that defended the e4 pawn such as Qe2,Nc3,d3 etc.
Believe it or not Re1 is favored over all other responses very much it is the most played/popular move. The reason why is becuase it has other function's. Another function it has is to vacate the f1 square which I highlighted in yellow. The importance of vacating the f1 square is shown in the above picture with the yellow arrows. Whites later on plan is to play c3 than d4 than try and move his knight from b1 to f1 (in some variations not all variations but some). You can see the route it usually goes Nb1-d2-f1 than it can go to either f3 or g3.
So lets pretend black does not play the correct respond which is either b5 or d6 lets say black plays 0-0. How do you respond as white to get an advantage?
I hope you guys/gals found the right continuation to punish black for his terrible mistake in this position. Castling is not the right move and hopefully you found the sequence to show black why his moves are wrong. I will admit I did try to trick you with the queen move;however, I had faith you find the right move if you did not than look at the below diagram so you can see why that move does not work in this position.
As you can see in previous positions the Queen to d4 was attacking both the undefended E pawn and undefended Knight in this position the E pawn is defended by the rook. Which means the only thing not undefended is the knight so the knight can retreat to f3 and attack the queen and white is simply up 1 pawn.
Blacks point of view in this position: Lets pretend black defends his e5 pawn successfully and lets pretend this time white does not see any problem and plays a bad move.
In the above picture white has just played the move 6.h3 which is a very multi-purpose move. Whites idea with this move is to control the g4 square to stop any of blacks pieces from going to g4. Maybe black had some idea's of playing his knight to g4 or even his bishop to g4 pinning the white knight on f3 to the white queen on d1.
This h3 move is a prophylaxis move that is restricting the black pieces.
The move h3 also allows white the chance to give his king some loft(escape square) so he does not get back rank mated later on in the game.
Surely this can not be a bad move. What do you think?
The move 6.h3 in this position is a terrible move. You see that is why chess is hard sometimes. Positions like this distinguish good players from great players.
A good player will know all the ideas of the move h3 and know all of its benefits giving loft, controlling squares, restricting pieces.
A great player will know the same idea's as the good player but the reason why they are great is because of their timing. They know when to play h3 and they know when not to play h3. In this position it is not the right time to play h3. The move 6.h3 does alot of things but what it does not do is protect the e4 pawn.
Which means black has a chance in this position to get a slight advantage can you find it? *Hint Defend than Attack*
Hopefully you found the sequence of moves which allowed black the chance to win the E pawn and gain an advantage in the position. If you are wondering what happens next. I will show you lol.
Does black get to keep his e5 pawn and stay 1 pawn up? Well actually many black sided players instead of trying to hold on to the pawn. They decided to let white waste their time getting the pawn back lol. You have to remember they nicknamed this line the Spanish Torture. You don't get away that easy lol. Your king is still in the center have to remember so if you try and save your pawn your king might come under fire. So thats why they decide to just let white waste his time recapturing the pawn to restore material balance while white does that black trys to get safety and improve their position.
In the above diagram I show you a few different lines that white can try and play against black after his faulty mistake. Usually black sided players do not mind in those positions and have slight advantage. I not plan on going that deeply through all of those lines because I'm more focused on the Marshall Attack as a whole than the offshoots lines that happen by mistakes. I just wanted to bring these lines to peoples attention so they at least know what to do if they find themselves in a position to get an advantage from a faulty 6th move. I will show a quick example of 1 nice continuation for black if white plays it. The reason I am showing this continuation is becuase it looks very similar to the Marshall Attack only difference is that it is a better verison becuase white messed up.
So that is a quick variation if white messes up his 6th move. That position looks very similar to the Marshall Attack the difference is in the Normal Marshall Attack black gives up 1 pawn in this variation black has not given up any pawns really so its much more solid and very nice position for black. You can tell by the arrows how limited whites pieces are and how much more active blacks pieces will be. As you can see from the green arrows black will try to castle than later on gain a tempo on the white rook with Bd6 activing the bishop on the nice b8 to h2 diagonal. In some cases black can drop the bishop to c7 and place his queen on d6 forming a Queen+Bishop battery trying to mate white on h2. Causing white to make more weaknesses in his position or causing white to get mated if he doesn't see it.
Critical Moment at move 7(Mainly for the Black sided player)
I will say move 7 is not that critical for white. The most common response at move 7 for white is to retreat his bishop to b3. If you can rememeber at move 6 it was attacked by the b5 pawn so white brings it to safety on b3 at move 7 which is not a huge problem for white.
On the other hand the black sided player faces a critical moment. The reason why is becuase at move 7 the black sided players have to figure out which path they wish to go down. The main 2 critical paths are with either castling or d6. Their are several main lines which can be played from either path.
The move d6 is the most played move/popular move. I did a database check just to see if I could make a list of some of the variations lol in the d6 line to give you an idea of some of the variations. Well I found their is over 25+ variations and inside those variations are variations. I didn't even play that many moves and a list of 20+ variations pop up so I changed my mind Ha Ha. I'm not going to show you a list of variations that come from the move 7...d6 by black. It would take me forever to make that list lol. Grand Masters have been playing these lines for centuries and have analysis this line to death really lol. So its not uncommon for it to have so many variations in it.
So instead of giving you a list of all the variations. I will try and give you maybe 1 or 2 variation names that people play from the d6 line that are popular.
- Chigorin Defence
- Breyer Defence
I will say their is some positive aspects about this. I mean at least you will not get bored and have the chance to find a variation you like. I mean with over 25+ variations lol The odds are in your favor that you will find a variation you like. Which that is if black plays d6 in this position.
The other move/path black can take is by castling not moving the D pawn yet. So that is important becuase you might not want the pawn on d6 lol. Maybe you want it on d5 Ta Da we are geting closer to reaching the Marshall Attack lol. However, we are not their yet white still has to make a move before we can be in the starting position.
Here we run into a problem as the black sided player.
The problem is its whites turn to move LOL. Yeah thats a pretty huge problem. If only they didn't have to move those basters. Its sad really but in this position white sided players have about 5 different moves they can play in this position at move 8. Now you might ask why is that a problem? Well the reason that is a problem is becuase you can only do the Marshall Attack against 1 of the 5 moves LOL.
So that means I have been teaching you a line that Frank Marshall created that you will never be able to play in your chess career becuase your opponents might play 1 of the other 5 moves LOL.
Your Welcome though I'm glad I can share this knowledge with you. So now you are more prepared to play this line that you will never be able to play. Well maybe if you are lucky you might get the chance to play it against someone. Maybe every 5,000 games you will get the chance to play it 1 or 2 times. Will be very exciting for sure. So now you know why the move 7...d6 is more popular than to castle for black. It simply is because they can't get the position they want. So they get frustrated and decide to just play the other lines which are more common and easier to get into. I mean white would be crazy to let you play the Marshall Attack again him it is a pretty good line.
So lets see the 5 moves white can play from this position and see which ones allow the Marshall Attack and which ones don't allow Marshall Attack.
This move allows the Marshall Attack
This move does not allow the Marshall Attack
This move does not allow the Marshall Attack
This move does not allow the Marshall Attack
This move does not allow the Marshall Attack
So lets go through each one and figure out why.
The main reason the Marshall Attack works against this variation is becuase of a few factors. The whites queen side is not yet development(hard time to get it developed) + the fact the move c3 is not as aggressive.
When you look at the above picture you can see factors I am talking about can't you? The whites queen side can not be developed as easy. In fact the white knight is limited in the squares it can go to. It can not even go to c3 because of the pawn on c3. The other factor is the c3 is not as aggressive(its not really hitting anything at the moment).
When you have all of those factors together it makes the d5 move rather good. The reason why is becuase whites pieces are not yet in their best of shape as of yet and d5 liberates blacks pieces so they can come more active in this position. Usually the Following sequence will happen after the move d5. Which d5 allows the loss of a pawn. The e5 pawn to be specific it is a pawn sacrifice.
Most of the moves played seem very simple to understand moves. If I remember right that is how the main line goes. I believe most of the moves are simple to understand from their. However, I will talk through it just incase you are confused.
At move 9 white takes the d5 pawn pretty straight forward black retakes with the knight.
At move 10 white takes the e5 pawn which white has under attack 2 times with his rook and knight. Black retakes the knight.
At move 11 The rook takes the knight and than threatens the black knight that is on d5. Rememeber light square bishop is hitting that knight as well so its double attack which is why c6 is played to defend that knight.
At move 12 white plays d4 trying to at least give some of his queen side active mainly the bishop. Black moves his bishop to d6 hitting the rook activing the bishop.
At move 13 the rook drops back. Black usually goes Qh4 threating mate in 1. Check below picture.
The best defence for white is to play g3 if white plays the move h3 black will do a bishop sacrifice with Bxh3.
It is clear that what black plans to do in this position is to mate white so yeah he will go for the attack. White will try to do defence and try and hold on to his 1 extra pawn.
So the battle will be over trying to mate and defend from mate in this position. Very juicy tactical position. I believe I will stop the opening theory moves in this position since its quite clear both sides have their advantages and disadvantages.
Advantage = 1 extra pawn, very solid pawn chain, If white can defend successfully the extra pawn may help him to win.
Disadvantage = Whites queen side is not yet developed and is having trouble getting developed, Whites king is very alone.
Advantage = Very active pieces, King is completely safe at the present moment.
Disadvantage = Black is down 1 pawn so he has to play dynamicly, He has to go for the check mate or find ways of gaining his material he lost back.
As you can see it will be a very interesting and exciting battle. After you get past the first 8 moves I would say the next 5 I showed here are not that hard to remember. Most of the moves from 8 to 13 are very logical moves. They deal with alot of exchanges so its easier to rememeber when you trade pawns and pieces etc.
Next I will be showing you the lines which make playing the Marshall Attack not a great choice.
This move actually helps prevent the Marshall Attack in a very unique way. In fact I would say out of the other 4 options this move can be the hardest of 4 to understand of why it prevents the Marshall Attack. I will show you how the move h3 does this.
Keep in mind why the Marshall Attack is played against the c3 line. The whites queen side is not yet development(hard time to get it developed) + the fact the move c3 is not as aggressive.
Now if we was to pretend black just tryed to go for the Marshall Attack and played d5 any way the same exchanges would happen but the position would look completely different take a look.
When you look at the position it looks completely different now doesn't it? Its the same sequence of moves but with the move h3 instead do you notice any key difference in this position other than the h3 move?
Do you see the difference in the position now with the highlights? Notice how many pieces of white have a red mark highlighting them. Only 1 piece of whites is inactive now. If you compared this position to the other position with c3 being played white queen side can be activated pretty fast. So in this position black has lost 1 pawn but he does not have compensation in the fact white's queen side is not lagging it can be developed rather fast. In the c3 line their was a pawn on c3 and white had trouble getting his knight and rook out for example. In this position the white knight can go to c3 than start trading off pieces like the knight on d5. If the knight on d5 goes than the pawn on c6 might become a target becuase of the Light Square Bisohp on b3. Do you see how white is more active in this position? This is why most players who see this line as black do not play d5 in this position instead they try another alternative move like d6. Going for lines seen in the d6 mainline variations.
As you can see the move h3 is used as a powerful waiting move to try and lure black into giving up a pawn. With the luxury of white being more active so its actually a very good move. Its in fact turned into a very popular mainline move.
This line is known as the "Anti-Marshall" It bascially stops the Marshall Attack in its tracks completely. The reason why might be pretty obvious by looking at the above diagram. However, like always I will go through it just to be very consistent.
Keep in mind why the Marshall Attack is played against the c3 line. The whites queen side is not yet development(hard time to get it developed) + the fact the move c3 is not as aggressive.
Well when you look at the diagram the move a4 is aggressive lol. It hits blacks b5 pawn. Which on the surface may seem not a huge problem but it really is a huge problem. The reason why is becuase the rook on the A file is not protected by black so he can't allow white to take the b5 pawn otherwise his a pawn will be pinned.
You might ask yourself what happens if black was instead of playing d5 right away played the move bxa4? Well white can respond with Bxa4 and now look at the problem below.
Now the D pawn can't move to d6 or d5 becuase the knight is hanging/being hit by the bishop. Not only that but now the bishop is also threating the tactic of taking the knight and having the white knight take on e5. Do you see how everything is just getting hit by the aggressive a4 move? Which is why the Marshall Attack can not be played after white plays the move 8.a4.
In this position it is very clear why d5 is not played. Unless you have a personal vendetta against your pawns and like losing material. Why would you play d5 here? The move d6 in this position is completely equal. It supports blacks e5 pawn nothing wrong with this move. In fact if you was to play the move d5 here in this position. I thought white had some tactics. It got me interested enough that I looked it up on a chess engine just to see if any tactical shots were able to be played. In fact in this position if black was to play the move d6 according to a chess engine the position would be (0.00) like stone cold even. It makes sence why though when you look at the move d6 it supports the center blacks is doing fine.
With the move d5 chess engine reads the position as (2.32) Basically black is down a piece lol pretty much with 1 crushing move. Can you find the crushing move for white here?
I will not tell you the move lol but hopefully you found it lol. Yeah its like a tragedy. The last continuation white can try for is the move 8. d3 so lets take a look at it.
Crosses my fingers lol Hopefully you start to see why the move d5 is not played in this position. The move d3 is not aggressive which is true. However, the move d3 does not limit the knight on b1 it is still able to develop to c3. Which means whites queenside is not really lacking in development. Which is why the move d6 is played and not the move d5 simply because losing a pawn in this situation with the move d5 is not that appealing since whites queenside can develop normally with out alot of issues. The reason why this is important is becuase black is banking on losing a pawn with the move d5 in exchange for this pawn loss. The compensation he wishes to have is a nice king side attack.
If whites queenside can develop normally its hard to justify such a loss of 1 pawn and its hard to pull off a king side attack becuase white will be able to get resources in fast enough to prevent an attack.
If whites queenside on the other hand can not developed that fast( which is the case with the move 8.c3) than the pawn loss has compensation in the form of an attack. In that situation the white queenside will not be able to fend off blacks attack so easy becuase of its lack of development and awkwardly placed pawns.
I hope you enjoyed reading my long article and have survived through it lol. Hopefully it helped you get some insight on a truly remarkable line Frank Marshall created which is still considered a very strong line/respected line.
If you get the chance to play it at least you will be better equipped with some of its themes and idea's it possesses. If you find yourself not liking the line for what ever reason perhaps you can take a look at other lines I mentioned along this article as well.
Thank you ever much, Congrats for making it through the long article with more knowledge, and Happy checking mating.