With one round to go, this was the position: The final heart squeezed West.

The last one squeezed West in the black suits.

Then the lead of the spade jack would squeeze West in the minor suits.

East had to win with the jack and return a heart, squeezing West in the minor suits as he did so.

This squeezed West in clubs and hearts, so the slam succeeded.

South won and now had some prospects of squeezing West.

This failed to drop the queen, but it squeezed West: he could not protect both black suits, and the game was made.

The club return went to dummy's nine and squeezed West in the red suits.

That would have squeezed West in three suits, a very rare event.

The only reason could have been to squeeze West in the minors.