PARD (dummy) - K J - Q 8 6

ME K 10 8 10 10

Q 9 4 2
Q 6 2
A K Q ? x
7

But where's the J? There can only be two possible explanations.

1. She didn't have it and didn't realize her partner had it, so she didn't try to cash it.
   
   
2. She had it, but was afraid I would ruff the fourth diamond, pull her last trump and then claim. Her plan would then be to endplay dummy into eventually letting her score a trump promotion with her remaining Q. If my hand were, say:
   
   K 10 x x   x x x   x x x   A x x
   
   then her play would have been right, even if she held the J.

1. Pulling the last trump.
2. Avoiding a diamond loser.

	PARD (dummy) - K - Q 8 6
LEFTY Q Q ? x -		RIGHTY - 5 ? J 9
	ME K 10 - 10 10

I lead the K from dummy and ruff(!) with the 10. Now I cash the K, pulling lefty's last trump and I have caught righty in a backward squeeze! He resigns by pitching the 9, which makes dummy good. Making 3 was worth 100% of the matchpoints (not to mention bragging rights). I couldn't have asked for friendlier opponents than these to enjoy the remainder of the matchpoints.

1. A more technically correct play at trick 9 would have been the K instead of the J, just in case righty was playing with me. I could have blown my chance in the end position by this impulsive play.
2. My other impulsive play of the K certainly should have cost, but it didn't. This was a simple case of failure to count the hand.
3. Some might have planned to make a safety play in the trump suit had righty followed to the second round. The standard trump safety play with Axxx opposite K10xx is to first play the A and then lead towards the remaining K10x, playing the 10 if second hand plays low. It is important to note that this would not have been correct on this hand. Suppose righty played low to the second round of spades and lefty won the 10 with the J. Another high diamond would again endplay dummy, still with 2 diamond losers in hand and a high trump out. The safety play would have been correct if there was still an entry to declarer's hand.
4. Cashing the AK was a matchpoint play to get all of our deserved uptricks. At IMPS, a more secure route to 9 tricks would be to win the J in hand with the K and try to ruff out as many diamonds as possible.
5. I don't know what went wrong in the diamond suit for the defenders. The standard signal on the first round of a side suit when there is visible shortness in dummy is suit­preference. On further rounds of the suit, they tend to show remainder count. Perhaps, if they were using remainder count after the first round of the suit, lefty would have figured things out.