Against 6NT, West led the ♥Q, and Declarer could count 9 top tricks.  A couple of Diamond tricks would get him up to only 11, so it looked like he needed Clubs to break 3-2.  Judging from what followed, one can only assume that this was the last board of the evening and that Declarer had a train to catch.  He concluded that the Clubs had better be 3-2, and announced to the assembled throng: “Making slam if the Clubs are 3-2, down one if they are 4-1”.  When it turned out that Clubs were actually 5-0 the protagonists negotiated a settlement of down two.

If Declarer had not been reliant on public transport and had given more thought at Trick 1 then he might have seen that the contract had chances even if Clubs misbehaved.  Our question is: At Trick 2, what is the only card from Dummy which enables Declarer to make his contract? 

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