How to react to a rook pawn that threatens the g2/g7 pawn when you are castled?

How to react to a rook pawn that threatens the g2/g7 pawn when you are kingside castled? 

What can be done?

Either push the pawn 1 square or maybe protect him with other piece or even better find a threat against your oponent and ignore the pawn.It depends on the situation

First off white will normally stop this pawn advance with h3 or h4 before the black pawn gets that far.

Perhaps a stronger player can comment, but if it does get that far I consider two main factors.  First has to do with files.  Will black's newly opened h file give his pieces scope to hit my king position?  What about the open g file?  (This is whether or not you want to allow a capture).

Secondly, how are the squares around my king effected?  Either way your light squares are going to be weak, but if you push there can be nasty pressure on your backrank where mate threats and sacs on h2 can be possible.

In this specific position pushing to g3 to avoid capture is much better than either capturing yourself or allowing a capture.  Your back rank is very safe currently, however if you traded, although there's no mate, you give black lots to play for (weakened king and pawns) that can last for the rest of the game really.

In this situation playing g3 doesn't hurt you significantly.  The big disadvantage, of course, is that Black now owns the g2 square and probably will for a long time.  Thus, down the road it could be dangerous for your King, and he'd be vulnerable to a back-rank mate.  But this board isn't anywhere near that point.

Like wafflemaster said, this should not have been allowed to happen.  White should have played h3 before the Black pawn got there.  That sometimes makes White a little vulnerable to attack along the b8-h2 diagonal, but in this case Black has his pawns parked on that diagonal and they'd prevent him from being able to put together a threat via that route.

I agree with the previous post. There is no simple answer to the question. There's too many factors that have to be considered . Yesterday I was playing against an opponent who pushed the g pawn forward and i was able to plant my queen on f3. Of course that was lights out: mate on the next move. I've also had cases where capture makes sense and still other where ignoring the pawn makes sense and letting the opponent capture is ok.

 I agreI was going to say that g3 is clearly best here.  But, after glancing at the position after g3 g5...Whites pieces look horribly discoordinated(of course blacks pieces are not out yet...But, they have teh space and can get them out comfortably.).  Make no mistake white will be worst no matter what he does it seems....Now that I look farther.  g3 g5 then white has n-e1-c2-d3(first idea I was looking for for white).  But, is it too slow as n-e1 is responded with d5 and the pawns around the king are once again horribly weak (in addition to those light square weaknesses.) if you play f3 or if you allow black to play dxe then there are even more light squared weaknesses...c4,d3 etc.  Basically white has already created too many holes in his position and in addition castled too SOON.  Sorry, I know that was probably hard to follow but the blood sugar is dropping.  Maybe I can put up a diagram after I eat lol.

My first idea as white to untangle was

I don't know if I agree h3 was better in the position before(if white had already castled).  After h3 g5 we see another weakness emerging.  Basically I think what is probably worst already

This is pretty much a long version of what pellik said... but anyway

remember too in that position white is better developed and a future central break is possible.  This means lots of wing advancing (if black follows up with a g pawn push) is actually hurting black by giving white targets and not developing in general.

If there's no mate or similar pressure, those black pawns are just weak. Viable pawn breaks + better development almost always = better position.  Getting to h3 is a nice little positional plus black can be proud of... now it's time to get down to business and work on that advantage with "regular" looking moves like just plain developing.

This is a strange position - how did it happen? The white white-squared bishop has been exchanged for the black black-squared bishop with no obvious pawn captures or black knight or rook moves. 

 I am not sure which position you are talking about.  But, black does not have weak pawns(except for when white is getting crushed by the attack).  And if you are talking about developing the white pieces....where do they go.  They all run into each other. 

and the fact of the matter is even if g5 doesn't work then the immediate b-g4 is simple and good

Is this a real position from a real game? What were the moves?

 Doesn't work in this position I don't think.  Seems like after r-e1 g5 threatening to win the knight with g4 is difficult to meet(just push g5 as black in any game and u are winning.  I think anyone knows this ;P)

 HAHA.....didn't even pick up on that.  Maybe that is why white is in such bad shape

They're a dynamic strength, but a static weakness.  If black allows the wrong types of trades and it gets to an endgame, white is better period.

I don't see a crushing attack, the nastiest thing I see is something like Bg4, Qe2 Qf6, Qe3 and black's attack is over in 2 moves flat.  It's enough for white to simply aim for d4 and develop in general and he's already doing what needs to be done to get an edge.

Let me note though I'm bias against static weakness... in fact I'm sure most players would prefer playing black here because of space and initiative and so on.  Also I could surely lose this position as white to some tactical oversight.  However I'd prefer to be white and try to prove my central break, development, and endgame odds outweigh my crappy kingside... that's the fun of chess though :) trying to show why your idea works and theirs doesn't!

Fair enough waffle...But, I think you are mistaken in thinking black is trying to win the knight(sure it would be nice) and that white only has an attack. B-g4 was playing that to make your pieces trip over themselves.

Also I don't mind going into an endgame here.  That h pawn isn't going to be attacked any time soon, it is protected by rook and bishop and there are not really any other weaknesses in the position.  However on the white side there is a weak a6-f1 diagonal(not that the bishop will necessarily be there. but those squares are weak), the d5 square(which is strengthened if you decide you want to advance your center)even the f4 square can possibly be weak(even in an endgame an interesting idea might arise with a sac there to possibly get the knight in and open the g file). 

or once again there is the simple idea of d5 while you are waffling about with your queen after b-g4.  But, of course the white position would probably be playable there(but def. worst imop-just how much is the question I would have)

Yeah, it's just my bias thing I'm sure.  I'm not very good at conducting an attack (or at least, not good at envisioning how one can come about).  So to me white looks cramped but solid.  The only target I see to pressure (much later on) are black's pawns.  Of course between now and then tons of chess will happen and who knows who will come out on top.

And in the end, no way would I allow black to play h3, I definitely agree about white's weak squares and the possibility that an endgame can favor black.  I'm thinking more about the bare bones endgame like K vs K or maybe K+R endgames where black will have no real prospects while now it's white who can try to go to work on the kingside.

I don't think black will want to play a pawn break in the center until he catches up in development. If the center pawns clear out it's white who's attacking :)

I was just curious what rybka thought about the position....alhtough this is exactly the type of position which rybka probably gets wrong.

at any rate it thought the best line after b-g4 was a draw.  I forgot about that b7 pawn.  So if white takes the b7 pawn there is a repetition.  q-f6 actually looks like an interesting try but which leads to an (interesting, but) equal game.