CONTRACT: 4 South
OPENING LEAD: Q (top of a sequence)
Four possible losers: two spades and two diamonds.
Line of play: establish the club suit to discard one or two spade losers.
Trick 1 W: Q, K, A, 6
Trick 2 E: 4, 10, J, 7
Trick 3 W: 2, 3, J, A
Two tricks have already been conceded to the defense and two more may come from the spade suit unless declarer can establish the club suit.
The only critical distribution of the clubs is a 4-2 break which requires a safety play. Two entries are needed to the dummy to perform this play.
Trick 4 S: A, 2, 6, 3
Trick 5 S: 6, 4, K, 3
Trick 6 N: A, 9, 6, J
Trick 7 N: 2, 10, K, 2
Trick 8 S: 4, 3, 10, 5
Trick 9 N: 7, Q, Q, 5
Declarer finaly leads a low heart to dummy's jack to discard one of his losing spades on the club eight.
This line of play wins whenever trumps divide 3-1 (50 % probability) or 2-2 (41 % probability) but loses if they break 0-4 (9 % probability).
Declarer makes his contract.
The defense takes three tricks: one spade and two diamonds.