The rule is for defenders
Alfred Nobel, he of the prize and dynamite, said, “Second to agriculture, humbug is the biggest industry of our age.” As you are aware, bridge is full of adages that are aimed at defenders. But some less experienced players think that they also apply to declarer -- humbug. That belief cost a game contract in this deal. South was in three no-trump. After West led a fourth-highest club two, what should have happened? North was right to open one heart, not one no-trump. Strain to show a five-card major. Here, North had no spade stopper, no tenaces and a comfortable rebid. South’s twono-trump rebid invited game, showing a decent 10 to 12 points and something in the unbid club suit. North had an easy raise.
The original South immediately remembered “second hand low,” so he played dummy’s club four and took the trick with his eight -more humbug, since the contract could no longer be made. Too late, declarer counted up his winners. He saw six: one heart, two diamonds and three clubs. Another four tricks were establishable in spades, so South was not worried. At trick two, he led a low spade toward dummy’s 10. However, West knew that defenders usually play second hand low. West took the next spade and exited with a club to dummy’s ace. Eventually declarer went down two. As you have noticed, South, after driving out the spade ace, needed a hand entry to cash the remaining spades. Since his only side winner was the club king, he had to win trick one with dummy’s club ace. Then he could have played on spades and cruised home.