Hello everyone.
I'm currently "reading positional decison making in chess" by Boris Gelfand where the author submits a game from rubinstein against schlechter. As he comment the game, he reported the move 13.Bb5!! as one of the "greatest move in chess history" and ... no more explanation about it. Can someone enlighten me and explains the idea behind this move? Here is the begining of this game :
lichess.org/study/3QYPRk89.
http://www.chessgames.com/perl/chessgame?gid=1119757One of the comments on the thread gives Razuvaev's analysis of the game. His comment on the move was: <An astonishingly deep decision. It is important that now Black's pawns will be posted on white squares and the black squares will be at the disposal of White's better developed pieces. Now 13...b6 is bad, as after 14.Rhc1 Bb7 15.Ke3 Black has no good continuation>
It stops cold Black's Queenside development. Bd7 hangs b7, and Nc6 allows white to degrade the pawn structure by Bxc6. The move Schlechter played, a6, might be forced. But that is exactly what Rubinstein wished to provoke! B7 becomes a target and it becomes very difficult for black to develop and get his queenside pawn majority rolling. Rubinstein was an endgame player par excellence.
Its basically the refutation of the entire 9...Qa5 line. All of black pieces are tied down. White can do whatever he wants.
It really is a subtle point, but I think I understand the intention. The idea is that in this structure (grunfeld like) a lot of play will revolve around control of the c-file for both sides. With White's move 13. Bb5, he induces a6, weakening Blacks queenside and really making it hard for Black to develop in an easy way. Black would ordinarily like to play b6 but he can't after playing a6. If Black tries b5, then White will reply a4. So while Black figures out a good way to develop his knight and bishop quickly without losing a pawn, White can gain influence over the c-file and the game.
Of course it's one thing to understand the intention behind the move, and another altogether to execute on it and convert this tiny weakness into a full point haha - especially at such a high level.