Four spades was reached by way of a very reasonable auction. West led the ten of hearts. East won the ace at the first trick and returned the three of hearts. Declarer won with the king and paused to take stock of his contract.
There was a very good possibility that a trick could be lost in each suit which would be one trick too many. At any rate, trumps were the first order of business. Declarer started with the king to guard against the possibility of a singleton queen. Both defenders followed low and declarer led a spade to the jack, which held while East discarded a heart. The ace of spades was cashed, leaving the queen of trumps outstanding in the West hand.
The ace of hearts had already been lost and the queen of spades was a certain trick for the defense. The ace of clubs was a potential loser, as was a diamond trick. But declarer had a counter play. The five of clubs was led from the North hand and East found himself caught in a Morton's Fork Coup.
The name is derived from Cardinal Morton, Chancellor under King Henry VII of England. It was Morton's duty to collect taxes for the Kings royal treasury. His approach towards tax collection was that if the subjects lived well, it was obvious that they had sufficient income to spare some for the king. On the other hand, if they lived frugally, they must be saving money and therefore could easily afford to pay their taxes. In either case, the royal subjects found themselves impaled on "Morton's Fork".
And so it was with East. If he ducked the club lead, declarer would win the king. The North hand would be entered with a diamond to the ace and the queen of hearts would provide a resting place for the last club in declarer's hand, thereby eliminating the club loser.
Winning the ace of clubs was no better. Eventually the queen of hearts and the queen of clubs would become tricks upon which declarer would discard small diamonds, thereby eliminating the potential diamond loser.
Had the West hand held the ace of clubs it would have been
necessary for declarer to start clubs by leading towards the
North hand first. So how did declarer know to play clubs the way
that he did? Go back to trick one and two. West led the ten of
hearts and followed with the nine at trick two. This looks very
much like a doubleton. East won the ace at trick one and
returned the three. His selection of the three from among five
possible cards likely has some meaning. In the event that the
ten of hearts was a singleton and West could ruff, East was
asking for a club return to gain entry for another heart ruff.
Declarer has only to pay attention in order to be able to make
the right play.
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