This is aHand:

"If it looks like a duck and quacks like a duck, we have at least to consider the possibility that we have a small aquatic bird of the family Anatidae on our hands."

-- Douglas Adams

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In today's contract of three no-trump, declarer has only seven top winners, but unless the defense can get either spades or diamonds going very fast, South will be able to establish the hearts for the two extra tricks he needs.

When the spade 10 is led, South plays low from dummy and can take the first trick and go after hearts at once. But if he wins the spade and crosses to a club in dummy to play a heart toward his hand, East will fly up with the ace and clear spades. West will be in position to cash out three spades when he gets in with the heart king, and there is nothing declarer can do about it. Cashing the clubs will not succeed as long as West pitches one diamond and one heart.

So what can declarer do about this possible scenario? The solution is rather unintuitive, but it is both elegant and logical. Simply duck the first spade (a play that would be easy to find if South had king-third of spades rather than his actual holding). West will probably continue spades, but declarer can win and drive out a heart honor. If West wins, he has no re-entry; if East wins, he has no spade left to lead.

The question of whether to duck the opening lead in a suit where you have two stoppers is not an easy one. Typically, the play is sensible when there are two high cards that need to be driven out, with no second danger suit.