This deal was played In a knockout match (IMPs) in the 2011 World Championships in Holland. At team scoring, the key is to make the contract (don't worry about overtricks). South held:

J 10
Q 9 5
Q J 9 5
A Q 6 3
Partner opens 1, you respond 1 and end up in 3NT (no opposing bidding).
 

A 9 6 A 10 7 2 A K 10 9 8 4

J 10 Q 9 5 Q J 9 5 A Q 6 3

The opening lead is the 4 (your opponents are playing fourth-best leads).

In notrump, you should count winners. You start with four sure diamond tricks and three side aces. When you play low from dummy, East wins the K and returns the 5 to your jack, LHO playing the three. It sure was nice to hold the J, 10 and 9 of spades!

This spade trick gets you up to 8 and you have numerous chances for a 9th trick. Let's say you unblock dummy's high diamonds and then run the 10. Unfortunately it loses to the jack and LHO clears spades (RHO following with the deuce).  Your thoughts?

Spades are certainly 5-3. Whether or not you can trust the opening leader, you probably should trust RHO. He won the K, returned the 5 at trick two, and now has followed with the deuce. Expert defenders return their highest from a remaining doubleton, and their lowest if they have three cards remaining.

Think of 3NT as a "race against time." You need to take your 9 before they take their 5. It looked like an easy race, but you are still stuck on 8 tricks, meanwhile they are threatening to take 5. LHO has two good spades to cash, and the defense has already won two tricks (the K and the J). You can't let LHO in again (that would be his third trick and he has two more to cash). So, you are in dummy (with the last spade stopper) and now face this position:

-- A 10 7 2 -- 9 8 4

-- Q 9 Q J A Q 6

You have only two hearts left in hand, because you threw one on the third round of spades. Now what?

If you repeat the club finesse, you are doomed if both the king and jack are offside. Will you take it?

My students tell me that finesses never work in my classes or articles. Here, there is no reason to take the club finesse. If RHO has the K, he presents no problem; you can just win the A and give him a club--he is expected to be out of spades.

Also, playing the A picks up KJ doubleton offside (the king will fall now). And lastly, even if LHO started with KJx, you still have chances by running your remaining diamonds. If West also has the K, he is in big trouble. Let's look at the real deal from Holland:

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

West led a spade to East's king and a spade was returned. Declarer unblocked dummy's high diamonds and passed the 10 to West's jack. West cleared spades, but declarer was smart enough not to repeat the club finesse (you can see that it would have meant instant defeat). Declarer smartly took his A and cashed his good diamonds. West was dead. He had to keep his K, and he had to keep the K protected. So, on the last diamond he parted with a spade winner. His last 4 cards were a good spade, the high club and the KJ. Declarer now knocked out the club king and claimed nine tricks. That's how you play 3NT.