Iremember to this day one particular deal from the Schools Cup back in 1980. I’d bid to Six Hearts and ran my trumps. At trick 13, my two of Clubs became a winner, after both opponents had thrown away Clubs. My opponents shot disappointed glances at each other, as if to say ‘Why on earth did you throw a Club?’. Then, the reality dawned: West had had to keep a Heart guard and east had had to keep a Diamond guard. In an archetypal Double Squeeze, neither could keep the Clubs.
Here is the classic Double Squeeze ending: West has to throw a Club, to prevent dummy’s King of Hearts from promoting. Dummy’s King of Hearts can now be released, having served its purpose. east also has to throw a Club, otherwise declarer’s King of Diamonds is promoted. At trick 12, declarer leads over to the Ace of Clubs, felling the King and Queen, whereupon dummy’s lowly two of Clubs scores the last trick. Clubs is said to be the Pivot Suit, the one that both opponents guard.
An opening Heart lead would defeat Six Spades on our first deal, but, after east led a normal Queen of Diamonds, declarer could succeed.
Declarer won West’s Diamond lead with the King and led the Queen of Spades, east winning the Ace and switching to the King of Hearts. Winning dummy’s Ace, declarer cashed the Ace of Diamonds and ruffed a Diamond, isolating the guard (so only West guarded Diamonds).
Declarer could now say to himself ‘West guards Diamonds, east guards Hearts, so neither can guard Clubs’. He ran all his Spades. On the last Spade, West had to reduce to two Clubs to retain his master Diamond. Dummy’s Diamond could now be discarded, leaving Ace-kingtwo of Clubs. east also had to discard down to two Clubs, to retain his master Queen of Hearts.
At trick 11, declarer led a Club to dummy’s Ace-king and scored the last trick with the deuce of Clubs. Slam made—as if by magic.
On our second deal, can you make Seven Spades on a passive Spade lead?
Declarer drew trumps in three rounds (West throwing a Heart) and had two main chances for a 13th trick. The Queen of Hearts might ruff out, setting up the Knave. Or the Clubs might split 3-3.
Declarer cashed the Ace-king of Hearts, then crossed to the King of Clubs and ruffed a Heart. No good —east discarded a Diamond. Declarer now cashed the Ace-queen of Clubs, hoping for an even split. No good—west discarded a Diamond.
It seems as if declarer is a trick short, but watch what happens when he leads his last Spade. West must discard another Diamond, to retain his Queen of Hearts. Dummy’s Knave of Hearts can now be discarded (having served its purpose). east must also throw a Diamond, to keep his master Club.
Having squeezed both opponents down to two Diamonds, you cash the Ace of Diamonds, cross to dummy’s King and win the last trick with the five of Diamonds. Grand Slam made.