For the 6th month in a row, our Real Deal comes from the 2018 U.S. Team Trials. South, Vulnerable against not, held:

 K103  
 Q742  
 AQ3  
 AJ2.
 

RHO dealt and opened 3. As they say, "it is dangerous to bid, but it is dangerous to pass."  South overcalled 3NT, raised to 6NT by partner. How should you play after a diamond lead?

A654  A5  K2  KQ975

K103  Q742  AQ3  AJ2

In notrump, I recommend counting top tricks. Here, you can count on 11 (clubs are sure to run). How should you try for the 12th?

One declarer won the K and played the 5 at trick 2. Do you like that play? The preempter could have the K, but these days, a white on red preempt doesn't really show anything. It must be better to play on spades. Why?

If spades are 3-3 (or QJ doubleton), you have 12 tricks that way. Admittedly, a 3-3 break is less likely than the 50-50 K play. But, even if spades aren't 3-3, there is a great second chance. If the player with long spades has the K, you will fall into your 12th trick.

Here is the Real Deal:

Vul:North-South Dlr: East	A654  A5  K2  KQ975
Q872  KJ86  8  10864		J9  1093  J1097654  3
	K103  Q742  AQ3  AJ2

As you can see, the declarer who led a low heart at trick 2, went down. West took the K and there were only 11 tricks. Declarer's team lost 13 IMPs (the other table was in game) instead of winning 13.  In a different match (all matches used the same deals), declarer led a spade to the 10 at trick 2. It lost to the queen, and West returned a spade. Declarer won the K, cashed the clubs and the A and then took his diamonds. This was the remaining position:

	A6 5 -- --
87  K -- --		--  109 J --
	3  Q Q --

On the play of the last diamond, West has to abandon one of the majors. As long as spades were 3-3, or the player with the long spades had the K (as here), the contract makes. This is a much better shot than putting all the eggs into the K onside basket.