When you choose the neutral trump lead to protect you holdings in the remaining suits, you find the following dummy opening on your left. The declarer wins and draws another trump, with partner following with 2 and 10 H. Declarer now leads the JC, ducked by you, followed by another club which you now win with AC, partner giving 6 and 2 of clubs. The critical point of defense has been reached. What is your next lead? You get 25 out of 25 if you get it right.
The first thing is defense is to try to understand declarer's possible distribution. How many spades do you think declarer holds and why? 2, 3 or 4. Well on your take out double and RDBL, remember partner passed. So he could not have 4 spades. Hence there is a strong probability of declarer holding 4 spades along with his 5 hearts which leaves him with 4 minor suit cards. Partner could not be holding a 5 carder club or diamonds which he would have chosen to bid on the RDBL which leaves him with a 3-2-4-4 distribution and the declarer to be left with a probable 2-2 minor holding. So you see there is no hurry to tackle spades for declarer can at most discard 2 out of the 4 spades leaving still enough spades for you. On the other hand declarer can discard both his diamonds on the KQ of clubs if you don't shift to the diamonds placing AD with partner to give you the only chance to beat the contract. That should be your thinking line in defense and rightly so for the declarer held. Your diamond J or KD shift would be a killing one to down the contract.
Let us get on to the next problem. You hear the following bidding sequence: You lead JC from the following hand to see the dummy opening on your left as under: J goes to Q, K and ace. Declarer comes with the spades ace in dummy and passes JH to your king. Again the critical point of defense has come. What do you lead next? What is your visualisation of declarer's hand? The vital question for you to resolve is whether after declarer has declared 5-5 or 6-5 majors, does he have a singleton club or diamond or possibly a void.
The proper thinking in defense should shed the light for you. First, can declarer have a void? No, for he used 4NT black wood. Next, can he have diamond ace? No - because other vise he would play it first and discard his other club loser if any on K & Q of diamonds declarer's deception in club was clever covering JC with QC to induce you in thinking he would be having a club loser. But clear logic tells you to play the diamond for the declarer if he has a losing club, must also lack the diamond ace.
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K1062 AQJ4 75
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76 KQJ83 A954
KJ 94 106 Q75
A87 J5 KQ104
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You Dummy You
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K1062 AQ 65
76 J943 K5
KJ94 KQ3 7654
A87 Q753 J10942
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S W N E
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1H DBL RBL P
Pass 1S 2H P
3H P 4H All Pass
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S W N E
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1S P 2NT P
3H P 4H P
4NT P 5D P
6H - ALL PASS
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