U.S. Championship Endgames pt. 2

Today we will continue our look at interesting endgames from the recently-concluded U.S. Championship.

I especially like the next example because it is almost like an endgame study.

Onischuk is famous for his exchange sacrifices resulting in favorable endgames - it is his trademark. He is an exchange down but has two extra pawns that are passed pawns. The b5-pawn will fall; while the rook is tied to the a-pawn, white can advance the e-pawn. After Kb4-Kb5 black's position is hopeless, so he has to do something urgent at this very moment. It is the 36th move, so I assume they were already in time trouble. Finding the saving idea is very hard.

Black's goal is to capture the a6-pawn. I imagine Kaidanov calculating B:g4 Kb4 Bc8, and after seeing that white defends the a6-pawn in time suspending the move. The next question in the decision-making process if we were perfect rational machines would be how to get the bishop to c8 faster. Then you would consider the h5-move - yes, a pawn sacrifice but only a temporary one as black wins back the a6-pawn. After winning the a6-pawn, the black rook gets back into the game and the position becomes equal.

The last example is from a game of the winner of the Championship - Hikaru Nakamura. The game reached the 110th move and still continues.

Lenderman looked relaxed and patient here. Hikaru was thinking hard and shaking his head from time to time, loudly sighing, indicating that he was not happy with where the game had come to. Although he is two pawns up, black appears to have set up a fortress. The black knight covers all the entrance squares and there is very little that white can do. Nakamura pushed too hard.

On move 121, b4 was already a mistake, after which it is white who has to be careful in defense. It is interesting that the draw is agreed after black's move a:b4. You might think that it was Lenderman who offered a draw. Lenderman was defending for the past 20 moves and hoped for a draw, while Nakamura tried to win this endgame. Therefore, the side with a slight edge or the side who is trying to win should offer a draw, in this case Nakamura. However, after b4 the situation has changed and if Lenderman had time to think about this change he would have realized that he is already better and probably would have refused a draw offer.

I was in the other room during this situation but other players came to the room and said that they didn't hear a draw being offered. Nakamura extended his hand and Lenderman shook it; in another version it was Nakamura grabbing Lenderman's hand. I don't know what is the final say here but clearly if a player of Nakamura's caliber offers a draw it is either he is worse or he is tired of trying to win an equal position. In this case Lenderman thought of the second interpretation and a draw was agreed.

Next week we will continue looking at endgames from the US Championship. As you can see from today's article the games were excellent and the players had plenty of fighting spirit in the endgame stage.