Black pins the White rook on c5 with his queen. But the pinned piece is attacked twice and protected twice, making it hard to see how Black can capitalize. Try our new strategy: consider whether an exchange or two might then make it possible to wheel other pieces onto squares where they can add pressure to the pinned position. The first exchange that suggests itself to Black is RxR, to which White replies QxR. The swap has created a new target, but more importantly it has cleared the way for Black to add a third piece to the action with Rb8-c8. White’s queen is pinned, so its only recourse is to go down in flames with QxQ. At first this might seem to leave things a wash when Black recaptures a7xQ, but there is a better reply: Black plays RxR+. This requires White to spend a move avoiding the check; then Black plays a7xQ. In effect the White queen was pinned to the loose rook behind it as well as to its king.

Black’s sequence here is an illustration of the correct use of the priority of check: if your opponent captures, sometimes it is best to hold off on the recapture and do any other damage you can that will inflict a check on his king. The recapture you postponed will still be there after the enemy has evaded the check, and in the meantime you will have taken more material than if you had recaptured right away. The position also shows again, of course, how a preliminary exchange of the pinned piece for a replacement can free up resources and allow you to put more pressure on the pinned position. Finally, here as in the previous position we see how two coordinated rooks are especially useful for that task, as one steps into the shoes of the other.