After some deliberation with myself, I have decided to publish this humiliating deal. I am the one who was humiliated. Playing in an online money game, I held:
94
K987642
KJ85
--

With nobody vulnerable, partner opened 1NT and RHO overcalled 2. I wanted to transfer to hearts, but this was a game with "no agreements" so I simply bid 4. LHO doubled and partner redoubled. A low spade was led and I saw:

AK73 A10 10973 A65

94 K987642 KJ85 --

I was hoping for better trumps in dummy, but all in all, this was a great contract. Even if I lost two diamond tricks, I'd be fine if I could hold my heart losers to one. Accordingly, I won the A and ruffed a club to my hand. I led a low heart and LHO followed low. I inserted the 10, expecting (from the double) that hearts were 4-0.

This was the full deal:

Vul:None Dir: North	AK73 A10 10973 A65
6 Q5 A642 KJ10872		QJ10852 J3 Q Q943
	94 K987642 KJ85 --

As you can see, this play did not work out well.

RHO won and the defense now got a spade ruff, A and a diamond ruff for down one (-200). Meanwhile, any old fool could have made 12 tricks! Just draw trump and play a diamond, making 6 (+1280). Talk about a costly mistake!

Everyone messes up sometimes. When good players do it, it's frequently because they had a mental "picture" of the hand that didn't turn out right. It can result in really spectacular mistakes like this one.

Updated: October 2020