Source: Winning tricks The Hand:
Q J 8 10 5 Q 10 9 7 4 2 K 8
A 10 2 A K 3 2 A J 8 Q 10 3
South played this hand in a contract of 3NT. West led 6 of spades and declarer played the 8 from dummy which held. He then played the 10 and finessed. West held off. When another diamond was led East showed out and declarer took with his A and played his J. West won with his king and switched to hearts, leading the jack. Declarer won with the ace and led a club to dummy’s king, which fell to East’s ace. East led a spade which West won with his K and returned a spade. Declarer won with his ace and after cashing in his K and Q conceded the rest of the tricks. This is a good example of how not to play a hand. Is is true South might have made an extra trick by his play if East had held the K not more than once guarded. (If it were twice guarded, East by refusing to cover would cause the suit to be blocked by declarer’s ace.) But why jeopardize the game for the sake of a possible extra trick? On the first lead, the 8 should be overtaken with the ace. This apparent waste material is justified by the value of the positive entry the play sets up in dummy, for it ensures that either the queen or the jack of spades will function as an entry to dummy’s diamond suit. After thus winning the first trick, the ace of diamonds is played out and the suit continued until it is established. The 4 hands:
Q J 8 10 5 Q 10 9 7 4 2 K 8
K 9 7 6 4 J 9 K 6 3 J 7 4 5 3 Q 8 7 6 4 5 A 9 6 5 2
A 10 2 A K 3 2 A J 8 Q 10 3