Against three no-trump, West led a club to the 10 and queen. Declarer naturally advanced the diamond king, which held. Next came the diamond queen to East’s ace as West completed an echo. Declarer ducked the club jack continuation, overtaken by West, who then cleared clubs with the nine, dummy discarding a spade.Declarer decided that West’s defense marked him with the spade king, so he tried to establish tricks in hearts. He advanced the heart nine, planning to let it run, but West covered. Declarer won with the heart king and led a heart back to the ace, felling the queen. The heart seven went to East’s jack.Declarer now had eight tricks — nine if the diamonds were coming in. Most East players would now return a safe heart, but look what happens if he does: Declarer wins and cashes the diamond jack, only to see West show out. Declarer’s only chance at this point is to find the spade king with East and endplay him to lead away from it — a chance that would succeed today.So, instead of a heart, East deviously plonked the spade jack onto the table. Now declarer had to make a premature decision. He was still spellbound by West’s club nine and rose with the spade ace, losing his game.Declarer might have played on spades earlier, but he should have considered East’s spade jack return more seriously. If the diamonds were coming in and West had the spade king, the spade jack would have to be from at least three cards — but why would anyone play the jack from those holdings?