It is easy enough to give a defensive signal; it can be much harder to interpret one. Try you hand at defending the following 1NT contract. The bidding is as shown below and you, West, lead your ♥5, with the following dummy appearing.
Dummy plays low, partner inserts the ♥10, and declarer wins the ♥J. Declarer thinks for awhile and then plays the ♦2. Here, there is no reason to play your king so you play the ♦8 (signalling odd count in your system), partner winning the trick with the ♦J. Now partner cashes the ♥A, everyone following. You hope that partner continues a heart, but that is not to be. Instead, he shifts to the ♣6. Declarer follows with the ♣8, you cover with the ♣9 dummy wins the trick. Next comes a low diamond ducked by both partner and declarer to your ♦K. You cash your ♥K, felling the ♥Q from dummy and ♥6 from declarer, partner discarding the ♠6. Now what?
You and partner are playing upside down attitude signals and discards, so the discard of his lowest card means he likes the suit, and high spot card means he does not. Moreover, when breaking a new suit in the middle of the hand, your partnership is playing BOSTON — Bottom Of Something; Top of Nothing. So the lead of his lowest card in the suit suggests he wants the suit returned; a high spot card means he does not. Partner pays very close attention to the signals he gives you, so you can trust his signalling.
What is your next play? Here are the cards remaining so far. (Your side has taken 4 tricks; declarer has taken 3):
Click on the link below to see the answer.
Defense is the most difficult part of the game of bridge, and interpreting partner’s signals is one of the most difficult parts of defense. It typically takes a close analysis of the spot cards that have been played (those pesky low cards that during the beginning part of your bridge career you were quick to ignore), the bidding, and the cards played to date.
It looks easy enough to return a club — after all, partner led the suit: doesn’t he want it led back? “Return your partner’s lead,” we were all taught as beginners. But it behooves you to take a very close look at the partner’s discard of the ♠6. What information is he trying to convey?
The ♠6 appears to be an ambiguous discard. If, playing upside-down attitude (low-like, high hate), your partner discarded the ♠2, the message would be crystal clear — “Partner, I have the ♠A.” Then the defense is easy: cash 3 spade tricks for down 1. But if instead declarer has the ♠A, the shift to a spade honor could be a disaster as it would allow for the easy promotion of a high spade dummy.
So you need to think hard about where the ♠6 lies within the possible spades partner could have discarded.
Here you see the ♠3 in your hand and the ♠4 and ♠5 in dummy. So only the ♠2 is missing. If declarer has the ♠2, then the ♠6 was partner’s lowest spade and you should promptly shift to a high spade. Is there any way you can tell whether declarer has the ♠2? Think hard about this before proceeding.
Indeed there is. To figure this out, you must go back to the bidding. North bid 1♠ in response to his partner’s 1♦ opening. South did not raise spades. With 4 spades, South would have raised. So South has at most 3 spades.
From the inference that South has at most 3 spades, it is easy to see that partner has at least 3 spades (13 – [3 + 4 + 3] = 3). Let’s say that partner had 3 spades NOT including the ♠A? Then, even if he had the ♠6 and ♠2, he would have a spade spot card higher than the ♠6. One very important rule of defensive signalling is that if you are giving a signal with a high spot card, you play the highest spot card you can afford. So holding, say, ♠862, partner would have played the unambiguous 8, not the ambiguous 6.
So from this, since partner did not pitch a spade higher than the 6, you can infer that declarer has the ♠2 and so partner’s ♠6 is his lowest spade after all. Get that ♠K out on the table and put the contract down 1!
But wait a second, why did partner return a club when he was in with the ♦J? Didn’t he want a club returned?
Here, BOSTON comes into play — bottom of something; top of nothing. Partner returned the ♣6. Is that his lowest club? You see the ♣3 and ♣2 in your own hand, leaving the ♣4 and ♣5 still hidden (recall that declarer played the ♣8). If partner had the 4 and 5 of clubs and wanted the suit returned, he would have played the lowest club, the ♣4, not the ♣6, to indicate he wanted to return. (If you think about it, you will conclude that partner must have at least one of those two lower cards) He did not play his lowest club so he was not playing bottom of something. His ♣6 was not asking for a club return.
(An irony — here a six conveyed entirely different meanings. In spades, it was partner’s lowest card, so it encouraged; in clubs, it was not his lowest card, so it did not encourage).
Here are all four hands:
Perhaps partner could have made things a bit easier for you by pitching the discouraging ♣10 (high hate) instead of the ♠6 in order to point you away from a club return. But that is water under the bridge. You had enough clues available to you to figure out what to do. How did you do?
This is a very difficult defensive problem. Don’t worry, they are not all that hard. But there comes a point during almost any closely-contested bridge hand where you really have to put your thinking cap on to figure out the best course of action. The reasoning process illustrated by this hand will not occur to you until you try to do it — take solace from the fact that the more you try, the easier it will get, and the better bridge player you will become.
— Tom Hunt