Games: Chess

This beautifully constructed problem was composed by the Dane Walther Jorgensen in 1973. It is White to play and mate in three, and it has one of the most surprising and paradoxical key moves imaginable.

White's main problem is finding a way to control d4. 1.Be3 would threaten 2.Qg5+ followed by d4 mate, but if lets the black king slip away with 1...Kf6. Another idea is 1.Nb5, threatening 2.d4 mate, but after 1...exd3 the knight is no longer controlling f5 so Black hangs on after 2.Qd4+ Kf5. With the knight on h5 (which protects f4) and the bishop on g6 (which protects e4) both unshakeable, White is beginning to run out of ideas.

On the other hand, there are some nice mates if Black can be persuaded to move something. If the knight moves from h8 to f7, for example, then White is ready with 2.Nxf7+ Bxf7 3.Qxe4 (or 2...Kd4 3.Be3); or if the knight on h5 moves, then 2.Qf4+ Kd4 3.Nb5 will be mate; or if the bishop moves to f5 or h7, then 2.Bf4+! Nxf4 3.Qg7 is mate.

So that's the trick. All we need is a waiting move. Well, we haven't used the rook on c1 in any of this, so how about, for example, 1.Ra1? No, there's no mate in two after 1...exd3.

Well, we now know what we're looking for: a rook move that provides a mate in two after 1...exd3. And the answer is wonderful: 1.Rd1!!

Now question one: why has White just allowed his rook to be taken with check? And question two: where's the mate after 1...exd3 anyway.

Answers: after 1...exd1=Q+ 2.Qxd1, Black cannot prevent 3.Qa1 mate; while after 1...exd3, White mates with 2.Qxe2+!! dxe2 3.d4 mate! The only other detail to fill in is 1...Kd4 2.Nb5+ Ke5 3.d4 mate. A superb problem that won a first prize.