| (b) | 2. R - B 7 ch | K - Q 5 ! |
| 3. P - B 7 | R - Kt 3 ch ! |
a very important move, as against R - K B 3, R - K 7 wins.
| 4. K - B 1 | R - K B 3 | |
| 5. R - Kt 7 | K - B 6 |
and White will finally have to sacrifice the Rook for the Pawn, or draw by perpetual check.
If there were nothing more in the ending it would not be of any great value, but there are other very interesting features. Now suppose that after 1 P - B 6, R - Q 3; 2 P - B 7, Black did not realise that R - Q 1 was the only move to draw.
We would then have the following position:
Now there would be two other moves to try: either (a) R - Kt 3 ch, or (b) R - K B 3. Let us examine them.
| (a) | 1. ........ | R - Kt 3 ch |
| 2. K - B 3 | R - B 3 ch | |
| 3. K - K 3 | R - K 3 ch |
If P - Kt 6; R - R 5 ch wins, because if the King goes back, then R - R 6, and if the King goes up, then R - R 4 ch, followed by R - K B 4 wins.