ACES ON BRIDGE

When South opens one spade, North’s call of two no-trump is an unlimited game-forcing trump raise. South’s jump to game denies both shortage and extra values, and North must pass since he has no undisclosed extras.

When dummy comes down, South sees that the contract may be in jeopardy if the diamond ace is offside. What is the right line after drawing trumps? South would lose out if he led diamonds first from the dummy. Specifically, if South put up the diamond king, West would take the ace and later capture the diamond jack with the queen. That would end any chance of winning a diamond trick.

The correct play is to lead a diamond toward dummy’s jack at trick three. This maneuver will force West to put up the queen if he has it. Later on, the jack can be used to knock out the ace. That means a heart can subsequently be discarded on the diamond king.

If East has the diamond queen, dummy’s jack will lose to it, but declarer will still be able to enter dummy with a heart and lead toward his diamond king. If East has the diamond ace, the king will provide the critical discard.

This play would not work if South needed the first or second trick in diamonds (or if West had led a heart at trick one). Since that is not the case, South increases his odds by leading first toward dummy’s jack and falling back on leading to the king, turning a 50 percent line into 75 percent.