North is on lead and NS need all the rest of the tricks.
In a sense NS have the rest of the tricks already, but it is impossible to take these tricks (because 2 club finesses are needed and the South hand has only 1 entry).
The Ace of diamonds catches West in an "entry squeeze" because, although a spade discard by him does not give up a trick (you already have 2 spade tricks!) it gives up an entry.
It is the extra entry that results in the extra trick.
After West discards a spade, South can overtake the K of spades with the A, finesse clubs, and then lead the 2 of spades to the 3 for a 2nd club finesse.
Geza Ottlik wrote extensively about various entry squeeze positions (among other amazing things) in a series of articles in The Bridge World called "The Way it Is" in the 1970s. The material from these articles made up the core material for "Adventures in Card Play" which is definitely the hardest (and arguably the best) bridge book ever written.
For whatever its worth, I don't think Ottlik would have considered Nick's position an "entry squeeze".
Fred Gitelman
Bridge Base Inc.
www.bridgebase.com

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