With six top tricks, game will be an easy make as long as you can come to three diamond tricks. Obviously, you need to preserve an entry to dummy, so it must be right to win the first club in hand. Perhaps, it looks tempting to lead a diamond to the king, but just suppose that wins, with East, say, ducking from a four-card suit. Then, whatever you do next in the suit, you will find you are an entry short to dummy to both set up and enjoy the remaining winners.

The answer, of course, is simple; you just have to duck a diamond entirely, making the defence win. You win the return in hand, knock out the ace of diamonds and can enter dummy with the ace of clubs for the remaining diamonds.