This deal was played In the 2011 World Championships in Holland. South held:

A Q 10
A 10 8 5
K J 4 2
K 6
Most players would open a 15-17 notrump. I can live with that, but I think this hand is really worth more like 18 or 19. The AQ10 combination is so much more than just 6 points (opposite the jack you will have 3 tricks if the king is onside; if you had only AQ2 in spades, you would need the king onside to fall singleton or doubleton). Also, the 10 with the ace (as part of a 4-card suit as opposed to a short suit) is a great value. The player at the table upgraded (with a strong club). After a waiting response and opener's 1NT rebid (showing 18-19), responder transferred to spades and the final contract was 4 on a small trump lead:

J 8 6 4 2 6 4 3 8 3 A Q 7

A Q 10 A 10 8 5 K J 4 2 K 6

Declarer has his work cut out for him. Maybe that upgrade was a bit too optimistic.Dummy's Q turns out to be a mostly useless card; a discard on the 3rd club doesn't do much for the South hand. That Q would be much more valuable if it were a red queen. Anyway, let's count our losers (S.O.P. in a suit contract). In spite of the low trump lead, the K could still be wrong--so maybe one loser there. It also looks like two heart losers and at least one diamond loser (maybe we'll have to guess the suit).

Entries to dummy are short, so right or wrong, declarer put up dummy's J at trick one. He wanted to remain in dummy to repeat the spade finesse in case RHO started with Kxx. The jack was covered by the king and ace. Declarer was now chagrined to see RHO show out on the next round of trumps. Doh! East started with a blank K. Squandering dummy's J turned out to be unnecessary and now there is a small trump to be lost (West started with 9753).

Is there any hope? Even if the AQ are onside, there don't seem to be enough dummy entries to pick them up. Our actual declarer played a low club to the queen and a diamond to his jack. This lost to the ace and the defense shifted to hearts. Declarer has to lose a trump trick and has lost the A. There is nowhere to throw dummy's heart losers. Down one?

Declarer won the A, played the K and ruffed a diamond. He played to his K and played his last diamond. LHO, who started with 9753 J97 A97 J98 threw a club on this trick. Eventually declarer lost his four tricks for down one. But, he could have and should have made his contract. It's magic. Take a look at the ending:

Vul: Both Dlr: South	8 6 4 6 4 8 A 7
9 7 J 9 9 7 J 9		K 2 Q 10 5 10 5 4
	10 10 8 5 K 4 2 K

Declarer has just won his A. To make the contract he should first cash his K (a key play). Then K and a diamond ruff. He cashes the A (while the cashing is good) as West follows with his last club. Then a spade to the 10 in hand to play the 4th diamond.

This time, West is helpless. Declarer has already taken the following 9 tricks (3 high spades in hand, the A, the K, a diamond ruff in dummy and the 3 top clubs). Dummy still has the 8 and has to score it. If West ruffs with the 9, dummy's 8 is high. If West doesn't ruff, dummy ruffs with the 8 for the 10th trick. The heart loser vanishes into thin air.

This was one of those rare suit contracts where declarer had to stop thinking about losers and instead count winners. By cashing his 3 clubs first and then eventually eloping with dummy's 8, declarer had a clear path to 10 tricks. It's like magic.