This deal was human dealt in the Swiss Teams on my recent Sectional at Sea (Quebec City to New York).

South held: 7
AQ7
AK965
KQ53
. Vulnerable against not, he opened 1. LHO preempted to 3, partner passed and RHO raised to 4. South doubled and his partner removed to 5. Everyone passed and the K was led:

54 K632 8432 A42

7 AQ7 AK965 KQ53

The defense led high spades, declarer ruffing the second round. If trumps are 2-2, declarer will be able to make 12 tricks. But, at IMPs, declarer needs to first make sure of his contract and not worry about overtricks.

If he lays down a top diamond and they are 4-0, he will fail in his diamond game. Accordingly, he should take a safety play to guard against East holding QJ107 (surely possible on the bidding). At trick 3, declarer should lead a low diamond towards dummy's 8. If everyone follows, declarer will win any return and draw trumps and claim. On the actual deal, West shows out on the first trump!

Dummy's 8 forces East's 10 and the J is returned.

Now what?

Declarer's work is not finished. Yes, he can win in dummy, finesse diamonds, go back to the K and finesse again in diamonds. But, what about the 4th club?

If clubs (or hearts) are 3-3, there will be no problem. But, if East has 4 (or more clubs), trouble lurks. If West has short clubs (two or fewer), he will have at least 4 hearts. There will be nowhere to put the club loser.

So, before drawing trump, declarer should test clubs ending in dummy. If they are 3-3, he can play diamonds and soon claim. A look at the full deal shows why it is necessary to play clubs before drawing the rest of the trumps:

Vul: N-S Dlr: South	54 K632 8432 A42
KQJ10832 JT85 87		A96 94 QJT7 J1096
	7 AQ7 AK965 KQ53

After two rounds of spades, South correctly plays a diamond to the 8 and 10. East returns a club and declarer plays three rounds of clubs ending in dummy. Had they been 4-2 the other way, there was never a way to make the contract. Had they been 3-3, declarer would play trumps and soon claim.

On the actual 4-2 break, declarer plays a trump (covering East's card), ruffs the 4th club in dummy and plays another trump, finessing and claiming a well-earned +600. (At the other table in the Swiss match, North passed South's double of 4 and collected only 100 on defense). On a diamond lead, West can actually make 4.

Note: Astute readers might be wondering why not try for 3-3 hearts instead of 3-3 clubs. Isn't that just as likely? Yes, it is. Declarer can win East' s J with the ace and play a trump, East splitting. Declarer can win and try ace, queen, king of hearts. If they split 3-3, he can lead dummy's 4th heart with decisive effect. However, there is no fallback plan if hearts don't break. Meanwhile, playing clubs works not only if they are 3-3, but when East has four.