In boxing terms, upper-cut applies to a swift, strong blow to the underside of the jaw, generally knocking the opponent out. An upper-cut in bridge is the play of a card forcing declarer to use a high card and thereby promoting a card in partner's hand to become a winner. The effect on declarer's hand possibly has the same effect as in the boxing ring – a knockout punch.

Consider the following hand in which you are sitting South. East deals and opens a weak 2 . You bid 4 and West bids 6,  the final contract. You lead the A which wins, partner following with the 7 and declarer the 8. How do you proceed? 

    Dummy (West) 

     ♠ A K Q

      J 9

     10 6 4 3

You (South)

    ♣ A K Q

♠ 4

A K Q 10 6 5 4 3

Q 9

♣ 10 9

Prospects for a second trick are bleak: The black suits offer no chance and you know from a count of the hearts that declarer has no more cards in that suit, so that's a dead end. Your only hope lies with the Q.

From his opening bid, declarer has 6 diamonds, presumably headed by the A K and with dummy's 4 cards making 10 cards in that suit, he is unlikely to play for a finesse. Time to use your imagination. Your partner is now also void in hearts and has a single trump. What if that trump is the J?  If you can induce him to use it to trump a heart, declarer will be forced to over trump with either the A or K, promoting your Q for the setting trick – a killing upper-cut. A word of caution, though: If you lead the K at trick 2, partner may simply discard a club or spade, so you should rather play a small heart, creating the illusion that declarer has the K. Partner will certainly ruff what he believes to be the opponents' winner. Declarer will, of course over ruff with hisK and bang down the A, hoping to drop the ¨Q. When the lady fails to oblige, he must concede the contract, one down. The full hand:

      North

       ♠ 10 7 6 5 3 2

       7

West

       J

      East

♠ A K Q

       ♣ J 7 6 5 4  

       ♠ J 9 8

J 9 2

       8

10 6 4 3

      South 

       A K 8 7 5 2

♣ A K Q     

       ♠ 4   

        ♣ 8 3 2

        A K Q 10 6 5 4 3

       Q 9

        ♣ 10 9

Here is another hand requiring thoughtful defense. This time you are sitting West. North opens with 2 ♠, partner bids 3 and South 4 ♠, which is passed all round. Partner wins the first two tricks with the A and K, you echoing with the 9 and 4 and declarer following with the ♥ 2 and 5. Partner continues with the Q. With your seemingly worthless hand, you face the following position:

You (West)

♠Q

-

J 10 9 6 5

        Dummy

♣ J 10 6 4 2

         ♠4 3

 

         10 8

         A K 4

         ♣ A Q 9 7

From the bidding, you know declarer has 6 spades and therefore partner has 4. If his spades are as good as ♠K 8 x x or even ♠J 9 x x, your spade lady may prove to be worth her weight in gold. Instead of uselessly discarding a minor suit card on partner's Q, trump it with your ♠Q, hopefully delivering the fatal upper-cut to the opponents' game contract.

Here is the full hand:

        North

         ♠ A J 10 9 6 2

         5 2

West 

          Q 3 2

      East

♠ Q

         ♣ 5 3

       ♠K 8 7 5-

9 4

       A K Q J 3

J 10 9 6 5

        South

       8 7

♣ J 10 6 4 2

         ♠ 4 3

       ♣ K 8

         10 8 7 6

 

         A K 4

        ♣ A Q 9 7

You can see how your upper-cut will ensure your side wins 2 spade tricks to defeat the contract. As with all other aspects of the game, defense requires careful thought and not a little imagination. Happy punching!