It is an easy trap to descend into

Saki, whose real name was Hector Hugh Munro, was a Scottish short-story writer. He advised: “In baiting a mouse trap with cheese, always leave room for the mouse.”

There is a nasty trap in this deal, into which many players would fall.

South is in four spades. West leads the diamond two: three, seven, ace. South plays a sneaky spade nine, but East wins with the ace and returns the diamond jack. How should South continue from there?

In the auction, South decided not to give free information to the defenders. He thought it most unlikely that diamonds would play better than spades, and opposite a one-no-trump response, a slam was improbable. If anything, four spades was a slight overbid, but either a good partner would hold a useful card or two, or an opponent would misdefend.

To the original declarer, everything looked like smooth sailing. At trick three, he covered East’s diamond jack with his king. However, West ruffed and exited with his last trump. Then South had to lose two more diamond tricks and go down one.

North was cheesed off. He mentioned that if South had played a low diamond from his hand at trick three, yes, he would have lost the trick and the next one when East gave West a diamond ruff, but he would have won West’s return, drawn trumps and claimed.

Also, North added, if it turned out that diamonds were 3-2 all along, losing trick three would have cost only an overtrick.

Always ask yourself what might go wrong: Is there a trap about to snap?