Imbalanced Forces, Part 2

Two minor pieces against a rook - a very tricky material balance. In one situation, a rook and pawn defeats the two minor pieces. In another, two minor pieces run circles around a rook and two - or even three, as we see in today's game - pawns. And differentiating between the two scenarios is not easy.

It all depends on whether the rook is able to find clear targets. If the rook can break into the opposing position, attack weak pawns, and create passed pawns. Then it can overpower the pieces - as in the following example:

A very nice ending. Black had to use very clever play to stretch White's position - with maneuvers against weaknesses on both sides of the board, tempo moves to force White into Zugzwang, and various tactical subtleties - for instance, the ways Black just managed to keep the e-pawn alive on moves 47 to 49.

GM Xiu Deshun | Image Wikipedia

On the other hand, there are situations where the rook is hopeless against two minor pieces. In our main game, like last week, we will see another encounter between Lev Aronin and Georgy Borisenko. In this game, the players entered a theoretical line which goes into such an ending. This was a relatively obscure tournament and involved relatively obscure players, but as usual in those days, it was a fascinating and intricate battle.

The game began with the well-known piece sacrifice line in the Slav, except that White varied with the sideline 10.Qf3. Of course this tactical move, hitting e4 and f7 while guarding c3, is critical. Now it has been worked out to a more-or-less a forced draw, but in those days they were still exploring the variations. One plausible line, with 12...Kc8 instead of 12...Nxg5, was played in the game, resulting in the following position:

White has two minor pieces against a rook and three pawns - technically, a large material advantage for Black. But experienced players know that this material balance (rooks versus minor pieces) is one of the least-amenable to simple bean counting. The rooks and minor pieces are such different pieces that the advantage will go to the side who the structure benefits the most. Here, unlike the Lenderman game, the minor pieces work together well to create threats; meanwhile the rooks cannot communicate and the black pieces are all disconnected. What results is a nice attack, in which the knights and bishops work together to create decisive threats.