Figure 6.2.9.7[Black to move]

Examine the White king’s position and the Black pieces that can be used against it. You have two rooks and a knight and therefore are looking for a way to coordinate two of those pieces in a mating crossfire. There is no way to mate just with the rooks (experiment and see for yourself), so look for a way to involve your knight. From its current post on h4 the knight can reach f3—and this signals the possibility of an Arabian mate. Indeed, if you did not have a rook already on f3 this position would be structurally the same as one of the skeletal positions we saw a few moments ago: Nf3+ would push White’s king to h1; then you would mate with RxR.

So what should be done with the rook now on f3? You really just want it gone, but moving it away without check loses the initiative and allows White to escape the mate threat. You therefore get rid of it with checks: 1. …Rf2+, 2. Kh1 (if Black instead interposes with Rg2, then White mates with Rg8xR+ followed by Rf1#), Rh2+; 3. KxR. The resulting position looks the same as the one pictured except that the f3 rook is off the board. By working solely with checks you have stayed in control of the action, and the nifty sacrifice at the end brings the king back to h2—so that now it can be checked again with Nf3+. Giving check with this move is critical, and was part of the point of what went before: after the first Black move described a moment ago (Rf2+) the rook had been cleared from f3, which was one of your goals; but this wasn’t enough because your next move, Nf3, would not then have been a check, and White could have played RxRg8+. With White’s king forced back onto h2 the position becomes easy: 3. …Nf3+, 4. Kh1, RxR#.