Defense in Bridge is a tricky business. There is so much to it that one keeps wondering how. Experts manage to come unscathed in their defense. One of the earliest lesson in defense that one can give to a beginner would be to stick to your potential winners and if required throw losers at the first opportunity. But then in defense there is more to it than meets the eye. So today's two short illustrations are a lesson in defense.See if you can pass the test.
In the first of the two illustrations your holding as west is as under:
The bidding proceeds as under:
As west you naturally lead the 9D as did the actual west and see the following dummy spread before you.
The play proceeds with declarer winning in dummy with AD and leading trumps, with partner winning with the AS, which is the marked singleton with him. Partner now cashes the KD and follows with the QD, the declarer following to all 3 diamonds: of course you need to discard on the 3rddiamond. Yourdiscard please? (Remember south holds at least 9 cards in the majors). So far this does not look to be amajor challenge in defense. Throwing an innocuous loser is basic defense. After your club discard,tenaciously holding to your precious Q J 9 4 of hearts sitting over the declarer. Partner now switches to the KC taken by declarer's ace,who now leads 10H from hand? Pouncing upon it with the JH, you naturally lead back your last club. Declarer ruffs it, cashes king of spades,plays the AK of hearts and ruffs his 4thheart (loser) in dummy making 8 tricks for his bid contract-1 diamond, 1 club, 2 hearts, 1 heart ruff, 1 club ruff in hand, the K of trumps and one from J10 of spades).
On the actual layout, the expert west defending got the contract 1 down. Can you spot your error, if you have made it? Yes, it occurred when on the third round of diamonds you threw what appeared to be an insipid club loser when you should have thrown a heart as did the actual west, who realised that the declarer has 5-4-3-1 shape and therefore needs to be forced with clubs to ultimately make your 9S a winner, or if declarer tries to draw trumps, you will have a winning clubat the end. South held: KJ 10 5 2, A K 10 8, 7 6 2, A.
In the second illustration, as west you are dealt: 6 5 4 3 2, J 9 8 7, 10, A 9 8. RHO started with a strong NT and in response to stayman denied a major suit. Next came Blackwood with RHO showing 3 aces to be put in 6NT. Leading passively, you are safe on a spade lead of the 5, partner following with the 7, with dummy spread out as under:
Taking the first trick in hand with AS, declarer cashes KQ of diamonds, partner playing the 8 and 4. As west yourdiscard please? Obviously a spade seems safe enough - not much to it. Declarer now returns to the spade winners in dummy - the J, Q and king. Your partner throws a diamond and 2 clubs. Declarer now tries the hearts-KH followed by 6H to his ace and low towards dummy and after a split second hesitation finesses the 10H successfully. Your partner parts with a third club. Butthe last heart squeezes him further as he throws the JC, declarer pitching a diamond. Now a club to the Q,K and ace by you gives declarer the 12th trick with the 10C. The east and south cards were as under:
With heart finesse, declarer had 11 top tricks as East was forced to throw 4 clubs to hold on to his diamond winners. But do you now spot your error as west? If you had not discarded a spade,that could have been your downing trick. The actual west was up to it and had retained the spade throwing instead a club - a far sighted defense indeed!

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Q 9 7 6
Q J 9 4
    9 5
  4 3 2
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W        N        E      S
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-        PASS     1D    1S
P        P        2C    2H
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P        2S     (ALL PASS)
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  West          North          North
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Q 9 7 6         8 4 3        K Q J 8
Q J 9 4         7 6 2       K Q 10 6
    9 5         A J 6          K Q 5
  4 3 2      10 9 8 7            4 3
====================================

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      East           South
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        7           A 10 9
      5 3            A 4 2
  J 9 8 4          A 7 6 2
Q J 6 5 2           K 10 7
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