Be careful not to give away vital information

Most players know about “balancing”: backing into the auction when the opponents stop low. “Prebalancing,” which requires fortitude and judgment, is acting with a light hand when you think the opponents are about to stop low and your partner won’t be able to balance.

Many experts embrace the concept. But your partner may not be able to tell whether you have a good hand or a light hand, and if you enter the auction when your opponents are likely to declare, you may give away vital information.

In today’s deal, East’s 2NT was “Unusual,” showing length in both minors. Playing at four spades South took the ace of clubs and returned a club. East won and led the ace and jack of diamonds. South won, took his king of trumps and led to ... dummy’s ace. The defense got a trump and a heart. Down one.

“I thought the man had a singleton somewhere,” South said, “but it might have been in hearts.”

South rightly placed East with a distributional hand, but after South wins the second diamond, he could lead a heart to dummy’s king and return a heart. If East could ruff, he would only be ruffing a loser, and if South took the ace, he could reasonably place East with 2-1-5-5 pattern. When instead East follows to the second heart, he probably has a singleton spade: South can play West for Q-x-x.

What if East passed at his second turn? NorthSouth would still reach four spades. South might make it, but with no roadmap from the bidding, I would expect him to fail.