One suit may tell about another

In this example deal, South is in three no-trump. West leads the heart eight (top of nothing), East wins with his king and shifts to the diamond queen. West correctly wins with his king and returns the 10, East overtaking with his jack. South ducks and wins the next diamond, West and dummy discarding hearts. How should South continue?

North’s two-club rebid was New Minor Forcing, indicating at least game-invitational values and asking South to describe his hand further. Two no-trump denied three spades and four hearts.

This auction kept dummy’s heart suit hidden momentarily, but resulted in the most damaging defense. Yesterday we saw that when North rebid a game-forcing three hearts, West led a club, the unbid suit. Then South took a safety-play in spades (cash the ace, followed by low to dummy’s 10) to ensure his contract.

Even now it looks as though dummy’s spades will provide the necessary tricks. However, a cautious declarer will cash his club winners first. Here he learns that West started with four hearts (presumably), two diamonds and two clubs. He seems marked with five spades. So declarer cashes his spade ace and plays a spade to dummy’s 10.

— March 18, 2025