Having a wire in a class setting

When you play a deal in a bridge class, you can often make certain deductions about the distribution of the missing cards. For example, if your contract is laydown with the trumps splitting 2-2 or 3-1, then you know that they must be 4-0. Do you take advantage of that wire? Certainly not! Find a guaranteed line.

In today’s deal, how should South play in six no-trump after West leads a top-of-nothing heart nine?

South’s two-no-trump response showed 8 or more points and a balanced hand. North’s four-club rebid was Gerber, the ace-asking convention.

South starts with eight top tricks: two spades, four hearts (given the opening lead) and two clubs. If the missing diamonds are 2-2 or 3-1, the contract is easy to make; they must be 4-0. In addition, if East has all four, the contract must fail. So, declarer can assume that West has all four.

Someone willing to take advantage of this deduction will win the first trick with the heart ace over East’s jack and run the diamond five — bridge is an easy game!

However, a player who wins trick one with the heart ace and plays a diamond to the jack suddenly cannot make the contract.

The right play is to win with dummy’s heart queen and continue with the diamond king. Suppose West wins with the ace (it doesn’t help to duck) and exits with a spade. Declarer crosses to his heart ace and leads a diamond, capturing West’s nine with dummy’s jack. Back to hand with a club, South finesses dummy’s diamond seven and claims.