Julia Child said, “I think careful cooking is love, don’t you? The loveliest thing you can cook for someone who’s close to you is about as nice a valentine as you can give.”

Your bridge partner will be very happy if you play bridge carefully, whether or not on Valentine’s Day. In this deal, how should South play in four spades after West leads the heart king?

In Standard American, the auction is straightforward. If you use two-over-one game-force, North would rebid three spades, and South, with a minimum opening, would sign off in game.

Declarer has four potential losers: one diamond and three clubs. He has only nine top tricks: six spades, one heart and two diamonds. South can hope that East has the club ace, or try to establish dummy’s diamond suit. But the actual layout is the one that South should fear. If he takes the first trick, draws trumps and plays on diamonds, East will win a trick and can shift to the club queen. Then, as long as neither defender tries to cash a heart trick, declarer will lose one diamond and three clubs.

What is the secret?

South must keep East off the lead. And the way to do that is not to win the first trick; let West take it. Suppose he continues with another heart.

Declarer wins with dummy’s ace and discards a diamond from his hand. Then he plays a trump to his ace before attacking diamonds. South takes dummy’s two winners, ruffs a diamond high, and draws trumps ending on the board. Finally, declarer cashes dummy’s remaining two diamonds, throwing club losers from his hand. In this way, South collects an overtrick, not an undertrick.