In the Sicilian, we tend to think of the queenside as Black's domain. Black's open c-file, which allows real pressure on c2 as well as support for a knight on c4, along with the easy possibility of expanding on the queenside by ...b5, generally gives Black the advantage in this sector of the board.
Nevertheless, in some situations White might take the initiative on the queenside. Sometimes White's majority of pawns there might become relevant, and the slight weaknesses created by Black's advances ...a6 and ...b5 can be exploited. This can be seen in a famous game from the 1995 World Championship - Anand's win, the first in the match, breaking a string of eight draws.
Viswanathan Anand | Image © Chess.com
In this game, the queens stayed on the board throughout (so it doesn't fit very well in the endgame theme of this column), but it shows some relevant ideas. Now let us see two of my games, both reaching the same endgame - indeed, the two games followed each other for twenty moves! This was not known theory, but actually my "own" theory.
In the summer of 2009 I first reached this ending against GM Vladimir Potkin, who later won the European Individual Championship:
A year later, I had the chance to play this same ending again as White. Although I realized that I had not obtained an objective advantage against Pokin, I went into it nevertheless. Black faced some difficulties on his way to equality, I ran no risk, and in any case I knew of no other way to gain an advantage in this line. I also hoped to improve on that game somehow. There is not much more you can ask of a chess opening, and in practice different players will always find a different - and often worse - way to play. The game resulted in one of the better endgames I have played: