Dlr: South Vul: Both J 7 J 7 6 5 3 J 9 7 2 § 5 2

K 10 A K 4 A K Q 6 § K Q J 10   A Q 2 10 9 8 10 5 3 § A 8 6 4

9 8 6 5 4 3 Q 2 8 4 § 9 7 3

Try it, even looking at all 4 hands, before reading on.

Correct technique is to win the heart ace, and play the DA, DK. This caters for the diamond jack falling in 2, when you can cash your diamond 10 for the 13th.
The diamond jack doesn't appear, no matter.

Now play off the heart king, and cash the spade king, and 4 clubs. Now play the spade ace, and queen. The position is:

- - - J J 9 § - - -

- - - 4 Q 6 § - - -   Q 10 10 § - - -

Immaterial

West says: "please claim"

73.40% awaits you if you do that.

A third of the field only made 12. They played off the 3 spades discarding the small heart from dummy, then the clubs arrived. Then a heart to the king. The heart 10 was good when West blanked the knave, but there was now no entry to cash it. Declarer played for 3-3 D's.

The method described above removes all guesswork. You will make 13 tricks if the D's were 3-3 all along, but more importantly, the squeeze operates against either defender holding the long hearts and diamonds.