Good idea, bad execution

North-South arrived in a very solid contract after a straight-forward auction. North’s cue bid to show an invitational raise or better is standard practice today for tournament players.

South won the opening club lead with his ace perforce and saw that his best chance to make the contract lay in the diamond suit. He would end with an overtrick if West held either missing diamond honor and might even bring in two overtricks if he caught a lucky diamond position. He drew trumps in three rounds, ending in his hand, and ran the eight of diamonds, losing to East’s jack.

East shifted to the nine of spades, which ran around to dummy’s king. South ruffed a club back to his hand and ran the 10 of diamonds. He was sad to see that lose to the king, and another spade from East saw West take two spade tricks for down one. What happened?

South had a good plan, he just executed it poorly. When East won the first diamond and shifted to the nine of spades, South should have played his queen.

This would hold West to just one spade trick whatever he did, and declarer could then afford to lose another diamond trick, if he had to, and still make his contract.