Last week, a beginning bridge player asked, "Is it ever right for a defender to *not* take a trick which he could take?"
Usually it is in the defense's best interests to take whatever tricks they can; however, there are exceptions. In the following hand, culled from Edwin Kantar's book "Defensive Tips for Bad Card Holders", declarer offers a trick to the defense -- a trick which they must not take.
South is playing a contract of six spades. Here are the hands:
North S: T62 H: AK87 D: 865 C: 732 West East S: S: J73 H: J9543 H: QT62 D: QJT74 D: 92 C: 986 C: QJT5 South S: AKQ9854 H: D: AK3 C: AK4Let's look at the hand from South's perspective. The South hand has no spade losers, no heart losers, one diamond loser, and one club loser. The low club and the low diamond could be discarded on the ace-king of hearts in dummy -- that is, if South can somehow "get" to dummy!
South knows that East-West hold three spades between them. If these three missing spades break two-one, then South can reach dummy as follows: play the ace-king of spades, which fells the jack, and then play a low spade winning in dummy with the ten.
However, in the above layout, South discovers upon cashing the ace of spades that East started with all three missing spades. Bummer! Observe that if South continues with the king-queen of spades to draw the outstanding trump, South will go down; there is no access to the ace-king of hearts in dummy, and so South must lose a club and a diamond.
After cashing the ace of spades and discovering the bad trump split, South needs to lead the spade nine. South's hope is that East will win the trick with the jack of spades. South can then win any return and play a low spade to dummy's ten, drawing East's last spade and providing the needed dummy entry. South gives up a trick which he doesn't need to lose, but in doing so he gains two additional tricks -- the ace-king of hearts which otherwise he cannot reach.
Now let's look at things from East's perspective. Declarer cashed the ace of spades, and partner showed out. Declarer now leads the spade nine, which East could win. But why did declarer do this? Clearly declarer could have drawn East's trump; but instead, South is generously offering East an undeserved spade trick. The only reason declarer would do this is to establish the spade ten as a dummy entry. Therefore, East should refuse to win the trick. If East plays the spade jack, South will make the contract; if East plays low and concedes the trick, South will be defeated.
As a final note, observe that if West holds the three outstanding spades, South can always make the contract. After cashing the ace of spades and discovering the spade break, South plays the nine of spades as before. If West wins the trick, then South can later use the spade ten as a dummy entry. If West plays low, then South can overtake the nine with dummy's ten and thereby gain access to dummy.