Again White has his rooks arranged in a battery along a file while Black’s are connected on the back rank. But this time the use White makes of the pattern is different, for it is Black’s rook on e8 that is under attack but protected by his king. True, it also is protected by the a8 rook; but then again, White attacks it twice. White thus begins with RxR+ (his only check, for those who keep track of these things). Black’s reply is forced: RxR. And now White has replaced a Black rook protected by two pieces with a rook protected only by its king—and which he still attacks. All that remains is to drive the king away with a check. Since White has vacated his rook from e5, the way is clear for him to play Bd6+. The king moves to g8, leaving the rook on e8 loose. White takes it with RxR+.

Lesson: when an enemy target is guarded by its king and another piece, try to get rid of the other guard so that only the king is left—for then a check may be usable to drive it away. Getting rid of the other guard may be a matter of attacking it directly, or as in this case it may be a matter of taking the target and allowing a recapture by a piece that ends up with only the king as a defender.

Incidentally, if you were looking for a way to blunder here, a natural method would be to focus too much on the idea of liquidating the rooks; as White you might imagine 1. RxR, RxR; 2. RxR, KxR and then you seem to be out of options. Our familiar point repeats: when you imagine even a short sequence, don’t forget the possibility of usefully inserting checks into the middle of it.