There are times when a declarer has to take cognizance of the contract as a whole and apply reasoning and logic to determine the trick taking power that he has and by doing so establish that extra trick which otherwise could doom his contract bid.
Many regular average type of hands keep coming in Bridge where the declarer has not much to think as the play is almost routine. But sometimes dummy play poses problems that may appear almost improbable to surmount. And yet where the declarer puts his thinking cap on, he can see light at the end of the tunnel. Let us learn by illustration. North south reaches a contract of 4S bid as under on the following hands held:
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North
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Q J 9 7
10 4
A 4 3
K 7 6 2
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South
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A K 10 6 4 3
K 8
J 8
A 5 4
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The bidding:
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W N E S
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- - - 1S
Dbl 2NT P 4S
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All pass
The opening lead is the KD. As south take it from there and plan your 4S contract.
First things first should be your line of thought as you view the dummy and know that you have 6 solid trump tricks, the 2 minor aces making a tally of 8 along with the KC to reach 9 out of your 10 tricks required. The method of counting losers after your winners shows 2 possible in hearts if the KH is off side, 1 in diamond and one surely in clubs. That makes 4 which is one too many for your contract to succeed. The vital question is how you can make a loser disappear?
Let's say you allow the KD to hold the first trick (East playing the 5) west now switches to a small trump, the 5S, to which you play 7S from dummy which east covers with the 8 to your top honour AS. Now what? Looking at west's informatory double, it is almost certain that he holds the AH which makes your contract dicey losing both heart tricks for sure which with a diamond trick already lost and an inevitable club loser staring across, your chance look slim.
But one hope still lies in dummy's 4 clubs which if they break 3-3 can give you a chance to discard one of your heart losers on the 13th club after trump extraction. But there is a big hitch here too. What if the lead goes to east in clubs who will surely fire back a heart to sink your chances of making 4S?
Now comes the skill and the reasoning behind it. Can you find it? The crux of the problem having been identified, it is for you to ensure that the club lead does not go to east when one inevitable club trick has to be given for the suit to run. You need to find a way to protect your KH. Have you found it? If yes, you can be proud of your good play. If not, here is the neat solution to it. After drawing trumps, lead the JD from hand which surely west has to cover as he holds KQ. Now comes your key play. Let him hold his QH as a trick. Do not cover it with the AH even if you are habituated to cover honour with a higher honour. Left on play west finds himself at the end of the rope whichever suit he leads is irrelevant and favorable as far as you are concerned.
What can he possibly lead from his original holding of:
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5
A Q J 9 2
K Q 10 9
J 8 3
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