Chessguy wrote on 07/31/07 at 18:50:36:


Yeah, but of course, it's not only Spanish positions, but it's just chess in general that if your opponent has some sort of pawn chain set up with its head on b5 or g5, you often play a4 or h4 to loosen things up, either to win a pawn, make inroads with your pieces, or open the a- or h-file.  One thing that makes the Closed Spanish so awesome for White is that due to Black's having weakened his queenside like this, White has options to play there, not only in the center or on the kingside.  It wasn't for no reason that Lasker and Steinitz and people of that era avoided moving their pawns.

In the following game http://www.chessgames.com/perl/chessgame?gid=1044287 Fischer playes 11.a4 this move seems standard in many the ruy lopez variations. Ofcourse it threatens axb but what it the real value of this move after black defends with Bb7 or something else? Is it just a move to gain space or is it more deep then that. Also when should you consider playing it? I have very little understanding of why this move is played and therefore I'd be happy for some beginner explanations for some talented people. Thanks!