It is necessary for White to gain a move in this position; in other words, White must try to transfer to the other side the onus of having to move. If then the Rook moves away from the King, it gets lost after a few checks, or if Black’s King plays to B1, the Rook is equally lost through Q-R6.
White plays therefore: 1. Q-K5ch, K-R1; 2. Q-R1ch, K-Kt1; 3. Q- R5, and wins. For example, 3. … R-B2; 4. Q-K5ch, K-R2; 5. Q- K3ch, K-R1; 6. Q-K8ch, and so on.
The Rook can win against a minor piece in exceptional cases only. In endings of ROOK AGAINST BISHOP the weaker King must take refuge in a corner square of different colour from that of his Bishop. For instance, Diagram 46:
Diag. 46
1. R-Q5, B-B5 (or R2); 2. R-Q8ch, B-Kt1, and Black is stalemate unless the Rook leaves the eighth Rank. Any outside square which is not of the same colour as that of the Bishop is dangerous for the King. Imagine the pieces in Diagram 46 shifted two squares towards the centre of the board, as in Diagram 47, and White wins with
1. R-QKt5 B-R5 2. R-Kt8ch B-K1 3. R-R8
The Bishop is lost, as it is Black’s move.
In endings of ROOK AGAINST KNIGHT, the weaker side loses, where the Knight is cut off from his King.
For instance, in Diagram 48, 1. R-Q5! In this “oblique opposition” the Rook takes four of the Knight’s squares: 1. … Kt-K8; 2. K-B5, Kt-B7; 3. K-K4, Kt-R6 (Kt-Kt5?; 4. R-Kt5ch! wins the Knight). In this ending there is always a fatal check at some point, and the position in the