Position of the day-19.9

Hey guys!

In the following position it's black's move, and it's not so easy to decide what the plan and move should be. The reason being that from first glance it looks as if white has tons of threats. 

So we base our descision on positional and tactical evaluation, as we have seen from my article.

Try reaching a good move for black here based on the same thought process:

i would have played e5 here

Please, support your claim with a positional and tactical evaluation.

first to block the Nxd5 or Nb5 which further moves to Nc7. at e5 if white plays Bb5 it would be a mistake i guess. at this stage white would retreat the bishop and we can further developing the bishop

Kd7!  just kidding; Nf6.  it develops a piece, it eyes the center light squares, protects d5 a 2nd time which is being attacked twice, it allows castling next move, unless Bb5 requires response.  4-5 moves later black may go Nh5 trying to trade for the bishop.  Black should consider how to respond to Bb5+. Bd2 would block the check, but also block the queen from protecting d5, and put black in a bind, requires a pinch of calcuation on 2-3 variations.

oops.  Black should beware of the Knight fork coming on c7 supported by the bishop.  which might be met by Qa5+ forcing the Knight back. wait, the LS bishop protects the Knight, so it doesn't have to retreat in that line. so maybe blacks best reply is to take the Knight now, at the position given above.

I just took a lesson yesterday so I'll give it a shot.  White is better developed with 2 pieces out as opposed to black's bishop.  White's pieces are more active, Although black's bishop is well placed.  Material is even.  White is threatening Nxd5.  Bb5+ isnt a real threat since  bd7 easily defends.  Blacks queenside is exposed and is behind in development so castling is definitely a priority.  However black's advantage here is space.  White has no central pawns while black has 2.  His d pawn controls the e4 and c4 squares.  So since space is black's advantage in this position then gaining more space with e5 appears to be the best move.  It gains a tempo on the bishop and now black controls the critical c4, d4, e4, and f4 squares.  This move makes nxd4 not possible as white will just lose a piece.  the inbetween move Bb5+ is defended by bd7 leaving white with the same problem.  If white retreats the bishop to e3 then Nf6 for black defends the d pawn and prepares castling.  Qa5 is an interesting move as well pinning the knight and threatening Bxc3 winning a pawn.  Although giving up the well placed dark squared bishop is probably a mistake and this threat can be defended.  So I will stick with nursing black's space advantage with e5.  Feedback is welcome.

Hi Matt,

About Bb5+ not being a threat- does black really easily defends? what could happen after Bd7 in this position? is everything's protected?

Bxc3!

Tactics: White has two threats. One is a double attack on the d5 pawn. Another is check with Bb7+. If Black blocks with …Bd7 then Nxd5 or Qxd5 wins material.

Space: White has a space advantage as the bishop controls the e5 center square. Black does not control any space. Yet…

Development: White leads in development with two pieces off the back rank and the light bishop semi-developed controls a long diagonal. Black fianchettos the dark bishop and the light bishop though semi-developed still controls two diagonals. Both sides are two moves from castling.

Quality of Material: White dark bishop and knight are free to move and threaten central and other squares. Black lack of developed pieces limits quality of material. Though, Black still has the e and d pawns which have potential to advance and control the center.

Material: Material is equal.

Requirements:

·         Protect the d5 pawn.

·         Get space.

·         Complete development.

·         Improve piece quality.

·         Maintain or win material.

Candidate moves to meet requirements:

·         …e6 protects the d5 pawn and opens a diagonal for the queen. But, it removes a diagonal from the light bishop and impedes development.

·         …Bxc3 removes a piece that protects the e4 square which results in a space gain for Black. It also reduces White development advantage because the bxc3 recapture does not develop a new piece. And, it creates double pawns for Black. But, it weakens potential for Black king safety as the fianchetto is gone.

·         …Bb7 develops a piece and protects the d5 pawn.

·         …Nf6 develops a piece and protects the d5 pawn. But, it blocks the dark bishop. Urgent.

·         …Qa5 protects the d5 pawn and pins the knight. But, it would be under immediate threat by b4.

·         …d4 protects the pawn and it attacks and forces the knight to move. And, a following move of …e5 would protect the d pawn and threaten the dark bishop, forcing another move.

·         …e5 attacks the dark bishop and it gains space with the f4 square. But, it blocks the Black dark bishop diagonal and does not protect the d5 pawn from existing threats.

Bxc3 meets at least five positional requirements:

1)    It mitigates the White threat of winning the d5 pawn.

2)    It gains space, the e4 square.

3)    It reduces the White development advantage.

4)    It gives White double pawns.

5)    It maintains material equality.

Finally, I just lost on time J

You're right I should rephrase.  If it is white to move then Bb5+...Bd7..Bxd7..Qxd7...and white wins a pawn.  If it was white to move then it is a threat.  But after e5 Bb5 isn't a threat anymore as he will drop his bishop.  Unless I am missing something.  So right now if white to move Bb5+ is a threat.

White has a space advantage?  I think it's pretty clear black's advantage here is space with his well placed d5 pawn, with the e5 pawn to follow.

Bxc3 does give white doubled pawns.  It also weakens all the dark squares around black's king as the kingside is the only side black can reasonably castle.  It also leaves white with the bishop pair in a wide open position.  Black has the opportunity to gain space here with e5.  And when you have space its generally a bad idea to trade pieces.  After Bxc3 black is definitely worse.

Matt, White definitely has a space advantage. True, Black is the only one attacking opponent squares with a pawn (e4 and c4). But, White is also attacking those squares. So, because Black cannot safely place a piece on either e4 or c4 then there is no space advantage for Black. However, White though not controlling opponent squares with pawns is unilaterally controlling two opponent squares with pieces (g5 and b5). True, they are not immediate central squares. But, it is more than zero space – which is better than Black.

Matt, I concede to both your points about Bxc3 losing the Bishop pair and compromising potential king safety. Still, there are many other advantages of Bxc3.

Black has the space advantage because he controls those squares with pawns allowing black to places his pieces on those squares.  White just contests them.  Controlling those squares with pawns is better and gives black the space advantage.  You don't gain space with pieces.

Matt, I think we have different definitions of "space". I understand space controlled by a pawn is more valuable than space controlled by a piece. But, I did not realize that pieces cannot control space at all. By your definition I agree with your assessment.

Philip, I'm calling a lifeline. What is the definition of "space"?

I came up with Bxc3 but not for the same reasons as already expressed. 

Rather, Bxc3 is also the only move I see that doesn't create an immediate material loss sufficient to win the game. 

Consider if black does nothing then: 1. Nxd5 wins the pawn. Bxb2 is not a sufficient reply because of 2. Nc7+ Kf8 3. Qxd8 OR 2. Nc7+ Qxc7 3. Bxc7

1. Bb5+ is also a real threat as 1. ... Bb7 does not defend so easily after 2.  Qxd5 Bxc3+ 3. bxc3 Bxb5 4. Qxb5+ and while white has doubled pawns, white's significant lead in development and black's weak dark squares mean it's pretty much all over by the crying for black. 

The only place for deviation that I see is that Bxb5 isn't forced for black, but what could possibly be better? 3. ... Nf6 4. Bxb7+ looks good enough for white to win to me.

Black is facing two immediate tactical threats. Both of those threats require the participation of the c3 knight. Both threats are winning for white. 

There's no need for positional consideration in my mind -- failure to take Nc3 concedes the game. 

As I understand it, a winning threat supercedes positional criteria. Bxc3+ is the only move I see that eliminates both threats.  

Kingpatzer, I'm having trouble following your variations. "Bxb8 is not a sufficient reply": did you mean Bxb2?

I side with friedman here;  Will pawns determine space? Not always.  Especially if they cannot be supported and maintained, then it all crumbles, and two open files in the center is more about bishop,rook, queen coordination and control.   e5 might look impressive, but can it last?  Bg3 saves the bishop; Nf6 will block the Bishops protection of e5; Ne7 is not the ideal square for the Knight;  Bb5+ Bd7, Qxd5, and Rd8 later-- white has the edge. 

Yes, sorry, Bxb2