Truly Ordinary Deal?

DO NOT look at the East–West cards, but look at the rest of it. You are declarer in 5 ♣. Ready?

This deal occurred on BBO yesterday, and I was declarer (playing with Prajwal, Guthi on my left, SP on my right). West leads the ♥ J, dummy playing ♥ 6, to East's ♥ A, and East returns ♥ 9: ♥ K, ♥ 3, ♥ 8. You play ♣ K and both follow with low cards. You then play ♣ Q, West taking the ♣ A, and East discarding ♥ 2. It seems pretty clear what your chances are, doesn't it? The diamond finesse needs to be right. No points of interest, are there?

So when West returns ♠ K, you take it with your ace, pull the last trump, and take the finesse. Correct?

Of course not. If it were so, you'd hardly be reading about it here. The thing to note is that you have ♠ J in dummy and West holds the ♠ Q. So what, you ask? Well, it's squeeze time.

If the finesse is working at all, so is the squeeze. So if the finesse is on, you can force West to play it when you lead towards dummy. Just cash your ♦ A and run all your clubs.

When you play your last club, you're down to ♠ 7 ♦ 8 ♣ 4 and dummy to ♠ J ♦ KJ. Hopefully, West is down to ♠ Q ♦ Qx. If he discards his spade winner, your problems are immediately solved, so he will of course bare his ♦ Q. So when you lead your diamond at the end, a low card from West can only mean he does not have the queen, revealing that East has it (this is called a show-up squeeze). So you don't finesse and play for the drop of the doubleton queen with East.

I spotted this play only after going down two. How did you fare?

You may now look at the East–West cards and note that on the layout this play fails too, as East has ♦ Qxx. But in view of his weak jump overcall, this play is important. And for what it's worth, I'd have gone down just one, not two, for a minor swing of 1.87 IMPs.

(Interestingly, if West is from Wackoland, he will have ♦ Q without ♠ Q, forcing you to go down in a contract every dipshit made.)