It is generally recognised that defence in Bridge is its most difficult aspect for it is much easier to play as declarer viewing half the deck than it is to defend not knowing which cards are held by partner and the declarer.
All that is helpful, for the defence is the bidding that has preceded the play and of course the opening lead from the partner that carries a message as to which suit the partner is interested in and what strategy should the defenders adopt in order to put the declarer's contract down. We are all aware that defence can either be active or passive - the active defence is generally adopted when the strong bidding tells them that the declarer's strength lies in a 2 suit distribution hand with probably a singleton or doubleton in dummy to facilitate an easy cross ruff in a suit contract. Here defenders fearing a side suit set up either lead winner to cash in, knowing the contract is too strong to the be downed or alternately, if the bidding has been hesitantly pushed to the game level, defenders put up a passive front and play a waiting game making the declarer work for establishing his winners. Those who recognize what needs to the done early are usually the winners for with foresight and imagination, they are also good in their timing and know well enough where to hit the declarer in his weak spot, failing which, being alert enough to change track in time when needed. Against such formidable defenders, the declarer has little chance to make his contract if the cards are not even remotely placed in his favour. Bridge is in the end a battle of wits where both the declarer and the defenders fight it out to the bitter end.
Our illustration for today is one such hand for the defence. Let me put the reader in the west seat and see how he copes up with defending a contract of 4H bid by NS as under:
The opening lead from west holding the following hand:
Is naturally the AC, whereupon the following dummy unfolds before you:
Your KC and QC win the first two tricks, partner following with 2C and 4C. As west how should you carry on? Partner's cards in clubs clearly spell out 3 in numbers leaving you at a critical point of defence where you need to concentrate hard and see from where you can find the winning defence. West's hand is a tempting one, isn't it? The singleton diamond is quite tempting especially as east gave the deuce of clubs. If east gets an entry, he can shoot back a diamond for west to ruff as the downing, trick number 2, with the AH being the downing trick number 1.
It is here where the thin line between average defenders and the good ones dictates the obvious difference. The average defenders are always in the majority. Are you one of them? Anyway did you lead a diamond next? If so, I am afraid you are an average defender. For the good defenders put their thinking cap and look far ahead for vital clues - that can guide them to a better defence.
Let us now analyse the prospect for the declarer and the defenders. The first and foremost clue is the point count of south. Remember his 1NT opening is on 12-14 H.C.P Now look at what are those? The AK of diamonds and the 2 major kings add up to 13 HCPs. This is a clue pointing to the fact that your partner east holds a yarborough. Therefore, your next lead - the singleton diamond, is pointless and more so-for if east by chance held the AD, the contract was a dead duck anyway. That leaves us with the next alternate, to think of. What comes to your mind? A trump. Well! This could be safe but not really helpful for the defence. The actual defender switched to a trump at trick 2 and lived to regret it, for the declarer stripped west of the AH and claimed his contract. What was the correct defence then?
Yes, now you get it. His asset was his length in trumps and all he had to do was to capitalise on it by continuing clubs. No doubt it would present declarer with a ruff and sluff but then the declarer's trumps shrink to 3 for the declarer held:
Holding off AH until the third will leave declarer or dummy with no more trumps. South was bound to lose trump control and with it the contract. But the fear of ruff and sluff is so promptly weighed upon Bridge players that even if it is the winning line they are confused - now they see it, now they don't.

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South       North
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1NT            2C
(12-14)
2H             4H
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    63
  A742
     8
AKQ975
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  AQJ9
QJ 109
 QJ 10
    J3
======

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 K 108
  K865
  AK97
  10 8
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