< Squeeze Hand: Play

Squeeze

To repeat, you are playing 6NT, matchpoints. You win the opening diamond lead in dummy and cash five clubs. Righty throws a spade, the nine of diamonds, and another spade. Lefty throws two spades and then, after some thought, the 6 of diamonds.
                 J85
                 A1098
                 Q8
                 K652

                 AQ
                 K3
                 AK32
                 AQ1094

You can simply play A and Q of spades to guarantee your contract. That's what happened at the table. But it costs you nothing to test the diamonds. On the K of diamonds, both players follow. So now you have 12 tricks with your long diamond. On the Ace of diamonds, Lefty follows and right pitches something.

It is probably reasonable to cross to dummy in hearts and take the spade finesse for the overtrick. The other possibility is a heart-spade squeeze, presumably against Lefty. That requires Lefty to hold both heart honors and the king of spades.

Placing those cards with Lefty is not unreasonable. Why else did Lefty throw a diamond? Can't Lefty read the diamond situation when partner throws the 9? Why wouldn't Lefty throw more spades if Lefty did not have a spade honor?

It does not hurt to play your last diamond and see what happens. (You can safely pitch spades from dummy.) The actual hand.

                 J85
                 A1098
                 Q8
                 K652
10652                          J4
4                              AKJ76
J965                           1032
10985                          K64
                 AQ
                 K3
                 AK32
                 AQ1094
So Lefty was triple-squeezed on the last club. The triple squeeze repeats, if you decide to play it that way. (You also cannot pitch a heart from dummy on the long club if Lefty pitches a heart.)