Source: the IBPA column service August 2013

A Q 7
K Q
K J 8 7 4
Q J 6
K 8 6
A 6
A 10 6 5 3
A 8 4
West North East South
3NT
Pass 6NT End

Opening Lead 3

After this simple auction, West led a fourth-highest three of hearts. Declarer saw that if diamonds were 2-1, then twelve tricks would come as a matter of course.

If diamonds were 3-0, then either he would have to guess well or he could cash the side suits
in the hope of gaining more information about the defensive hands.

Adopting the latter strategy, declarer took the opening lead in dummy and ran the Q to West’s K at trick two.

Rather than alert declarer that he began with 5 by continuing with the two, West exited
with a deceptive 5. After winning the A, declarer cashed the two club and three spade winners.

At first glance, not much had been gained. However, as the jack and ten of spades
had fallen from East the odds were three to one that this was from a three-card suit rather that from a four-card suit including the nine of spades.

So, declarer placed West with four spades, at least four hearts and at least three clubs – eleven cards in all. Consequently, as West could not hold three diamonds on these
assumptions, declarer played the king of diamonds next. When East followed the contract was his.

The 4 hands were:

A Q 7
K Q
K J 8 7 4
Q J 6
9 5 3 2
10 8 5 3 2

K 10 9 3
J 10 4
J 9 7 4
Q 9 2
7 5 2
K 8 6
A 6
A 10 6 5 3
A 8 4