Gunnar Hallberg, Swedish international and TGR regular, was East on this hand. He found the right play by using the most important tool of defence, counting the declarer's tricks.

Dealer South. Love All J 8 7 3 A 2 K Q J 5 J 6 4 A 6 5 K 10 9 2 6 5 4 3 K 8 7 3 2 10 9 8 7 K 10 8 2 Q 5 Q 4 Q J 10 9 A 6 4 A 9 7 3 West North East South 1NT Pass 2 Pass 2 Pass 3NT All Pass

Declarer played low from dummy on the club lead, East played the queen and declarer won the ace. Declarer played on hearts, East winning the third round with dummy discarding a spade. At this point many players would return a club. Now after West takes his king declarer has nine tricks.

Can you see any improvement for the defence? What Hallberg did when he won the king of hearts was to count declarer's tricks. South was bound to have the ace of diamonds - else why wouldn't he be playing on diamonds, rather than removing the ace of hearts as entry to them? Hence it was clear that South had seven tricks in the red suits to go with the ace of clubs, and a club return would obviously set up his ninth trick. South needed the queen of spades to make up his 12-14 1NT, which meant that the defence couldn't make more than two tricks there.

So East returned a diamond. This innocuous looking play scrambled the declarer's entries. If he won in hand to lead a club, he would never be able to cash his fourth heart. If he cashed the fourth heart first, what was dummy to discard? One spade had already gone on the third heart, and if he discarded another the defence could take four spade tricks when they came in with the king of clubs. The only other choice was to discard a diamond, but that would leave declarer a trick short.

Incidentally, if declarer thinks the defence will play this well, he should try the jack of clubs at trick one - his only chance being that West has led from the king-queen.