KQ
AJ732
52
A1032

AJ2
Q84
A83
KQJ6

The contract is 6. The opening lead is the 10.

It is not obvious to me how the hand should be played. Anyway, you play out your king and queen of clubs, with both opponents following. Now your slam is almost certain. If you want to follow the problem from the book, you should now plan your play.

Obviously, you can ruff one of your diamond losers. You can pitch the other diamond loser on the fifth round of hearts (ruffing the fourth round). So the only danger is a 5-0 heart break. If you lead towards the Q and Righty shows out, your queen loses to the king but you have good enough heart spots to take a double finesse in hearts for your extra trick (you make the AJ7 of hearts).

So the problem is, what do you do if your Q wins and Lefty shows out of hearts? Is there any hope?

Discussion/Answer