This happened at an ACBL Regional tournament last week. South is playing in a notrump contract. At trick twelve, the lead is in dummy. Declarer calls for a club, and wins in her hand with the Ace. She then says "diamond". West, without any pause, immediately says "accept the lead" and insists on winning the trick. North-South are not happy about this outcome.
It's not clear if Declarer knew which cards were winners and which were losers. Your ruling?
Does it make any difference if declarer's spade was the Ace?

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