Do you defend this way or that?

Alexander Graham Bell said, “Great discoveries and improvements invariably involve the cooperation of many minds.”

At the bridge table, accurate defense is sometimes the work of one player, but more often it requires cooperation between both defenders. One of the most important building blocks is the expectation that each partner will play the correct cards.

In this deal, for example, how should the defense proceed after West leads the spade four against South’s contract of four hearts?

Note that a pre-emptive opening does not deny a side-suit ace, although making that bid with two aces is debatable. North wondered briefly about responding three no-trump, but worried that he would lose too many spade tricks. Here, though, he might well have survived. Would East have started with his two top spades?

When less-experienced players have ace-king-third or -fourth in the suit that partner leads, they think it makes no difference whether they win the first trick with the king or ace — but it does. With ace-king-third, you must take the first trick with the king. If you win with the ace, then cash the king, you indicate that you started with that doubleton in the suit. Then it is partner’s job to tell you where his entry card lies, so that he can regain the lead either to cash the queen or to give you a ruff.

Here, at trick two, West should drop the spade 10, the unnecessarily high card being a suit-preference signal for diamonds. (With the club ace, he would have played his spade three.)