Even with all the cards in view, it is not easy to see how declarer can be prevented from taking ten tricks at four spades. It is true that declarer has four apparent losers—a heart, a club and two diamonds—but West seems certain to be forced to yield the game-going trick to South at some point during the play.
For example, if West starts by playing the K-A of hearts, declarer ruffs, draws trumps and leads the king of clubs. West can hold up once, but must win the second club, after which a club, diamond or heart return hands South the contract.
Nor is it any better for West to cash the ace of diamonds or ace of clubs at trick two. The diamond ace sets up declarer’s king, while on the play of the club ace, South unblocks the club king to insure scoring dummy’s Q-J.
Gordon, however, found the winning defense—and she did it without seeing South’s cards. After cashing the heart king at trick one and noting her partner’s three—denying a doubleton—she rightly concluded that declarer had a singleton heart.
Visualizing the actual setup (or one similar to it), she shifted to a low club at trick two! Declarer won with the king, drew trumps and returned a club. Now, however, Gordon was able to win and play the heart ace, leaving South with no recourse. After ruffing, declarer ran her spades, but the defenders scored two diamonds at the end for a one-trick set.
Gordon’s low club return had much to recommend it. If her partner had the king, all was well, while if declarer had three or four clubs including the king, nothing would be lost one way or the other. But if South had the hand she actually held, a low club at trick two was the only way to defeat the contract.