A quick review: “Unblocking is the process of playing a higher card to establish enough entries to make the necessary tricks. It sometimes can involve playing a high card in one hand so tricks can be taken in the other hand.” — Google

Last week we covered unblocking on defense. Usually, it’s the province of declarers. So here are some questions about how unblocking can help land a contract.

The key decision can come on the opening lead. You’re in 3NT with these cards:

                    NORTH
                    ♠️ A 10 3 
                    ♥️ 6 4
                    ♦️ K Q J 10 4 3
    `                ♣️ 10 6
 
                    SOUTH
                    ♠️ K 5 4
                    ♥️ K J 5 3
                    ♦️ A
                    ♣️ A J 4 3 2

West leads the ♠️Q. What do you play?

If you put up the ♠️A, you’re sunk because there’s no way you can run the diamonds on the board. Instead win with the ♠️K. Unblock the ♦️A and lead a spade to the ♠️A. Now you can cash five more diamonds and the ♣️A for nine tricks.

Occasionally you need to overtake honors. Again, the contract is 3NT:

                    NORTH
                    ♠️ A 3 2
                    ♥️ 6 3
                    ♦️ K Q 10 5 4 3
                    ♣️ 10 4
                    
                    SOUTH
                    ♠️ K 6 5 4 
                    ♥️ K J 7 6 2
                    ♦️J
                    ♣️ A K Q 

West leads the ♠️J. Your move. Of course you win in your hand. But don’t think that if you lead the ♦️ an opponent will play the ace. So, what do you do?

Overtake the ♦️J with the ♦️K. Now you can force out the♦️A and get back to the dummy with the ♠️A.

O.K., how would you unblock this suit for maximum tricks?

                    NORTH
                    ♠️ K 10 9 3

                    SOUTH
                    ♠️ A Q 8 7 4

You don’t want to take the fourth trick with the ♠️10 or ♠️9, so cash the ♠️A in case there’d s 4-0 spade break and unblock the ♠️10 and ♠️9 under the ♠️A and ♠️Q. Now cash the ♠️K and lead the ♠️3 to two more tricks.