Source: 
Boletines
This deal from the 2012 European Open Team Championship saw England’s David Gold bring home a tricky slam.
Board 18. Dealer East. N/S Vul
Gold was East and, after opening a 15-17 no trump, found himself declarer in 6NT on a Polish (low from an even number) lead of the four of spades. Gold won the ace and played jack and another club, on which North pitched a discouraging heart. What had looked to be a walk in the park had suddenly become more difficult.
At this level of the game, it doesn’t pay to place too much trust in an opposing signal, but it seemed that the discard was more likley to be from the ace than the queen here and, needing at least one heart trick, Gold played a heart to dummy’s ten. When that held the trick. He could of course have simply crossed to hand and led a second heart to the king, but there was a big danger that North had ducked the ace, and Gold found a much stronger line.
He played ace of diamonds and a second diamond to his king to see if the jack would appear. When it failed to do so, he continued with the two remaining club winners, throwing both hearts from the table. North was obliged to discard a spade and his last heart, so Gold cashed the queen of diamonds, crossed to the king of spades, and led the last diamond, throwing North in to lead away from the jack of spades at trick twelve.