Any chance to win is better than none

Peter Thomson, the Australian golfer who won The Open five times and died last month, said, “Every tournament has its climax, its winning moment. If you’re not watchful, you will miss it and lose your best chance.” This deal features a winning moment. However, it is necessary for declarer to recognise his best — well, only! — chance to make his contract. In golfing terms, if he misses the putt, he loses the tournament. South is in four spades. What should he do after West leads the club king: ace, two, four? I would be inclined to make a takeout double with that West hand, flawed though it is with only three weak hearts. But two clubs is one-dimensional — and on this deal should drive South into the right play. What information about the deal does declarer have? When East follows suit at trick one, South knows that the clubs are 5-1. Obviously, declarer will lead a trump — but, assuming he can make the contract, should he put in his jack or rise with the king? In isolation, finessing the jack is the percentage play. However, what will happen here? Yes, West will take the trick, whether with the queen or ace, cash the club queen and club jack, then lead another club so that East can overruff the dummy for down one. Instead, South must maximise his chance that West cannot get on lead. Declarer should put up his spade king. Assuming he wins the trick, he leads a second round and hopes that the ace and queen tumble down.