As West I led ace of clubs, East (Tam Townsend) played the seven and declarer the six. What now? If declarer has

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I have to play a diamond to enable my partner to cash his ace before declarer's diamond goes away on the king of clubs. But If declarer has

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I have to play another club, to prevent him using dummy's diamonds after unblocking the ace.

In practice I played a diamond, which as you can see was the wrong defence. Declarer took the ace and played four rounds of trumps. Then after my club return he took the king of clubs, cashed two diamonds and made the contract with the aid of the spade finesse.

Had I continued clubs at trick two he would have had a losing spade in addition to my trump trick. Best is for him to lead the queen of spades from dummy at trick three and play on spades, but when I can ruff the third and fourth rounds he has to go one down.

The clue to the correct defence is East's play of the seven of clubs at trick one. With declarer marked with at least ten major-suit cards this is a "count" situation, so with the three of clubs missing I can tell my partner has an even number. Hence I should have known continuing clubs was the right defence.

Between the sessions I had lunch with Zia Mahmood and his partner, the larger-than-life great French player Paul Chemla. Zia asked Paul about a hand, and said, "Why didn't you make the same bid as the rest of the room?" (known as sound tactics in pairs events). Chemla let out an ear-splitting cackle of scorn and said magisterially in his splendid fractured English "Zia, if I make the same bid as the rest of the room I would not be three times world champion".