BRIDGE

This week’s deals have focused on saving your partner from error. It’s well known that partners tend to do the wrong thing and need help, but even if your partner is world-class, prevent him from making a mistake if you can.

Cover the East and South cards and defend as West. Against South’s four spades, you lead the ace of clubs: four, deuce, five. You treat East’s low club as a suit-preference signal, suggesting strength in the low-ranking side suit, so you shift to the four of diamonds.

Dummy plays low, and East wins with the jack. Next, he cashes the ace. How do you defend?

Your partner may suspect that your ace of clubs was a singleton, but he can’t be sure. From his point of view, the defense may need to cash a third diamond.

To compel partner to make the winning play, throw your king of diamonds under his ace. He will have no option but to try to give you a club ruff. (Yes, an omniscient partner would have returned a club at the third trick.) Question: You hold: ♠ A Q874 ♥ AQ3 ♦ 92 ♣ K95. You open one spade, your partner bids two hearts, you raise to three hearts and he tries four clubs. Now what?

Answer: Partner’s four clubs are an ace-showing cue bid to try for slam. Since you have strong heart support and useful values, you must cooperate. A cue bid of four spades or five clubs is possible. I would jump to five hearts, asking partner to bid slam if he has a control in diamonds.