Sunday, August 19, 2007

Rook vs 2 Pawns

An interesting thought about these endings is, the side with the rook wins just as often against two pawns as it does against one pawn.

A rook vs 2 pawn(s) wins 43%, draws 40%, and loses 17% of the time.
A rook vs 1 pawn(s) wins 45%, draws 55%, and loses 1% of the time.

I. The side with the rook wins when...

Connected or Isolated pawns
    The rook's king can get in front of them
    The pawn's king is away, and the pawns haven't reached the 6th rank.

Doubled pawns
    Evaluate as you would Rook vs 1 Pawn... consider the pawn in front.

II. The side with the pawns wins when...

Connected pawns
    They both reach the 6th rank, and the rook's king is away.
    They're protected by their king, and the rook's king can't get in front.

Isolated pawns
    They're protected by their king, and the rook's king can't get in front

Doubled pawns
    Practically never.

The drawing technique for the side with the pawns, is to push only one pawn, and reach a drawn Rook vs 1 Pawn ending. The side with the rook should sacrifice his rook for the lead pawn, and then stop the other with his king.

Let's consider some interesting positions:

Exner-Leussen, White to move. Either Exner didn't understand that the only way to win was to get his pawn in front of the h-pawn, or he didn't realize that after Kd4 the black king would be forced to retreat.

The game continued: 64.Ra3? Kg4 65.Ke4 h3 1/2-1/2. The winning line was: 64.Kd4 a4 65.Ra3 Kg4 66.Ke3 Kg3 67.Ke2 Kg2 68.Rxa4 Kg3 69.Kf1 1-0.

Saemisch-Reti, Black to move. A rare oversight by two great players. Black missed the chance to cut-off the opposing king and thus score an easy win.

The game continued: 72...Kc4 73.Kf5 Rf1+ 74.Kg6 Rg1+ 75.Kf6 1/2-1/2. The winning line was: 72...Rf1! 73.h6 Rf7 0-1.

Karpov-Seltzer, Black to move. Amateurs often believe connected passed pawns are stronger than they really are. Black should have won this position.

The game continued: 67...Rxb3. The winning line was: 67...Rh6 68.b4 Rh5+.

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