ACES ON BRIDGE
On today’s deal, when South opens, West makes a simple overcall — being unsuitable for a jump overcall. Now North wants to show a decent raise in hearts, but he may not have the tools available to do so. However, he can use an Unassuming Cuebid. Whatever he does, South should reach the heart game; making it is more problematic, though.
On the lead of the diamond queen, South expects West to have six diamonds and can infer the threat of a diamond ruff against him. If he wins the diamond ace to play on trumps, his diamond king may get ruffed away, after which he will be doomed. So, he must win the diamond king at trick one; now he wants to draw trumps. But who, if anyone, will have the singleton heart? Surely West.
To guard against that player having the singleton ace (the only relevant singleton), declarer wins the first trick in dummy, crosses to hand with the spade king rather than the club ace, and leads a heart. Now West’s heart ace beats empty air. He can give his partner one diamond ruff, but that does not cost South a winner.
Note: If South crosses to hand with the club ace, West can give East two ruffs, using the club king as the entry for the second ruff. It would be a pity to have negotiated so many traps but to fall into the final pit!