Hand 1. N/S vul, South deals (hands rotated).

	852 753 AKJ74 K3
	KQJ107 AQ9 10 8754

South	North
1	2
2	4
Pass

North and South have no agreements, so they end up in a somewhat thin game. West leads the 2 to the K and A. South does not have much to do besides trying to ruff clubs in dummy, so he leads a small club to the 2,K,A. East alertly returns a small spade to the K, West following. When South continues clubs, East overtakes West's 9 with the J and plays A 9, West discarding 2. The position is now:

	-- 75 AKJ75 --
	J7 Q9 10 87

West's diamond pitch is interesting given dummy's imposing holding. It seems that West might be under some pressure if South runs trumps. On the penultimate trump, West discards the 10, dummy 5, East 6. On the last trump, West agonizes before discarding the 4, while dummy discards 5, East 6. What is the situation?

One clue is West's first discard of the 2. Often a defender's first discard will be from a five card or longer suit. West may have had diamond shortness, but then the contract is probably hopeless anyway, and West would have had an easier time discarding. So assume West started with five or more diamonds. Since he led the 2 and discarded the 4, he probably started with three or more hearts. This means his shape was 2353 and the five-card end position is:

	-- 7 AKJ7 --
-- ? ?xxx --		-- ?? ?x Q
	-- Q9 10 87

Suddenly, the contract is unbeatable if South can guess who has the Q! Suppose West had it. Then South plays J,A,K, and East is squeezed in hearts and clubs. If East had the Q, then South plays A,K,J for the same squeeze. The full hand:

	852 753 AKJ74 K3
63 J42 86532 1092		A94 K1086 Q9 AQJ6
	KQJ107 AQ9 10 8754

It turns out the contract cannot be defeated with seven tricks remaining due to a rare situation called a compound guard squeeze. The compound squeeze is the following situation: Declarer has a running suit (in either hand) and has squeeze threats in all the other suits. One of dummy's threats can only be guarded by LHO, while both defenders can guard both of the other suits. When declarer cashes the penultimate winner in the running suit, LHO cannot unguard the suit only he can guard, so he must unguard another suit, leaving RHO the sole guardian. This leads to a double squeeze around the suit both defenders still guard, consummated by the last winner in the running suit. A small example (declarer leads the A and discards a small diamond or club from dummy):

	-- AJ Kxx Kxx
-- KQ QJ9 QJ9		-- x 876 876
	AK -- Axx Axx

In the actual hand, spades is the running suit, and diamonds is the suit only West can guard. Consider the end position with seven cards left:

	-- 75 AKJ74 --
-- J4 ?xxx 10		-- 1086 ?x Qx
	Q7 Q9 10 87

When South leads the Q, West clearly cannot toss a diamond. If he tosses a club, South has a double squeeze around hearts. If he tosses a heart, ordinarily South would have a double squeeze around clubs, but this would fail due to the lack of a club entry to the club threat. However, South still prevails due to the heart position, which is called a guard threat: If West tosses all his hearts, then South can take a heart finesse against East for an extra trick.

	-- 75 AKJ7 --
-- J ?xxx 10		-- 108 ?x Qx
	7 Q9 10 87

When South plays the 7, West has three losing options:

• Toss a diamond to give South four diamond tricks.
• Toss the 10 to allow South to squeeze East in hearts and clubs on three rounds of diamonds.
• Toss the J to allow South to finesse against East in hearts. The guard position in hearts saves the day and allows South to make 4 on a compound guard squeeze.

What actually happened: South had a feeling that if West had the Q, he might have discarded a heart on the last trump much quicker than he did. Nevertheless, he went with the 5-2 odds and took the diamond finesse, losing the contract and a great story.