Figure[White to move]

Look for any captures White can make. Observation one: White can take Black’s knight with his rook. Observation two: Black’s queen guards the knight. Observation three: Black’s queen guards other things, too—including the bishop on f6, which White also can capture. So now the remaining question is the order of operations best used to take advantage of Black’s overworked queen. White can start with NxB or with RxN. We have seen that the usual choice would be to start with your less valuable piece, in effect offering it up as a sacrifice with the threat that you will make a worse capture afterwards. But that principle doesn't always hold. Let's think through its application here:

(a) White could begin with NxB+, forking Black’s king and rook. Now Black plays QxN, seemingly allowing White to follow up with RxNc8. But not so fast: once the queen moves, the knight at c8 still is guarded by the rook on f8. So White actually loses the exchange with this sequence. Correct play for White instead is...

(b) 1. RxN—this time capturing with the more valuable of his attackers (and indeed making a temporary sacrifice of the exchange). If Black recaptures QxR, White now has NxB+—not only a capture but a fork of Black’s king and rook, allowing White to win back the exchange that he sacrificed at the beginning of the sequence. White emerges a piece ahead.

The lesson: when you see that an enemy piece is trying to guard two pieces, think carefully about which to take first; imagine each capture and its consequences. Move order matters, sometimes making it better to start by capturing with your more valuable piece after all.