The art of signalling in defence is not every Bridge player's forte. For Defense in Bridge is never easy unless the dummy exposes nothing better to do than playing the only obvious alternate. Of course the Defence signals are standard in all those systems where the players don't resort to an alternate system of signalling like the odd-even signals, upside down, leviathan discards, and so on.
But playing standard signals, the order of preference should be borne in mind to be first, the attitude signal ie where the lead by partner suits the other for encouragement or not. If yes, a normal high card like 7 and above will show liking for continuation. However, if the first signal for attitude is a low card like 5 and below, it shows discouragement, but does not in any way mean shifting to the lower of the remaining 2 suits in a trump contract. Then the count signal comes to help partner determine the card distribution between declarer's hand and partner's. The cards played low high shows odd number of cards held with high-low cards showing even number. The last defence signal in order of preference is the suit preference signal, ie showing preference to the higher of the remaining 2 suits by an unusual high card thrown and vice versa. The signals need to be viewed in this order of preference unless it becomes too obvious that a particular high or low card shows immediate preference signal like dummy holding a singleton in the opening suit lead; now an unusual high card shows immediate suit preference signal for the shift to the remaining higher suit and vice versa.
With the above explanation, let us learn by example. Our illustration for today is a problem for the Defence. Sitting west you hold.
The bidding starts from your right with 2S weak which is passed out. On lead clamouring for an extra trick in spades via heart ruff if possible, you lead the AH. Partner play's the deuce on it.
What are the implications here? The deuce obviously is not encouraging but shows odd number of cards, whether singleton 3 or 5.The first is impossible, so west can foresee that declarer holds 3 with partner signalling odd number of hearts held - most likely to be 5 since 3 would give declarer a 6-5 hand in majors which does not conform with his 2 spade weak opening. Seeking a ruff you play out the other heart taken by declarer's king. But now partner plays 3H. What do you make of it? Obviously having given the count and denial and of a heart honor, partner's 3 of hearts should be taken as a suit preference signal for clubs.
Declarer now leads a low spade. Your first action; you can take the AS and proceed with the clubs to seek an immediate entry that partner has signaled for, to enable him to give you a heart ruff. Do you? Of course you can't be seeking another entry in partner's hand via the KD to get another ruff. For by then declarer is also in a ruffing position with dummy ruffing as well. But there is no harm to duck the first trump to severe the trump link between the 2 hands. Moreover, you would also be able to judge partner's signals in trumps. Partners play 7S first, followed by the 3S. Trump echo usually indicates a 3 card holding. But here, knowing declarer's bid of 2S promises 6 cards, partner cannot possibly hold more than a doubleton in trumps. Weak opening, in majors have been occasionally made on 5 carders but not likely in the first seat opening. So placing partner with a doubleton in trumps, what do you make of his trump echo? Surely there must be a reason behind it and the reason is obvious-partner is showing an avid interest in diamonds too, for now the 7-3 signal is again a suit preference signal providing an honour in diamonds. Although the signals given by partner are conflicting with his heart plays indicating club strength (attitude - suit preference) while his spade plays indicate diamond strength, the first 7S thrownpreferring diamonds. Partner can either have AC or KD or possibly the KD and KQ of clubs.Since KD is almost certain, you lead back a diamond to partner's KD who gives you the ruff in hearts and when you next lead a club, partner's KQ provide the setting trick for a well-planned Defence that materialised when west drew the right inference from partner's defensive cards, reading the signals perfectly.
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North (Dummy) -
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K 4 A 10 2
Q J 5 A 6
Q 9 7 3 A J 6 4
10 9 5 4 J 8 7 2
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