Bridge Note: The reasoningis simple

Dummy play in Bridge has always been the game's key characteristic. For it is one of the most significant reflections of a Bridge player's caliber. A number of Bridge books by experts have been written on the subject enumerating the various techniques of dummy play from the simple finesse to the compound squeeze. But the fascination of Bridge lies in the fact that each deal presents its own challenge in the making and it is imperative that a declarer realizes very early the different options he can avail of and then by a reasonable assumption pick on the winning line for making his contract.
Some lines are easy, some a bit tougher to foresee. See if you can match the winning line picked by the declarer in his contract detailed below where NS reach a little slam bid as under:
The opening lead from west is the JH. One look at the dummy and declarer can see that this is a tricky contract which leaves several options to choose from by placing the key cards and making the timing right.
Let us place the reader in south's seat. How would you go about it? The JH is taken by east's KH and east now shifts to the 9S, covered by JS, west's QS taken by dummy's KS. Of course you need to take the inevitable trump finesses by playing from dummy and going up with the JD. The trump finesses succeeds the critical point of the play has been reached. Counting your losers, you can view one probably in clubs provided the club finesse is not on. Then there is a possible loser emerging in spade although the lead of the 9S has somewhat mitigated your spade losing scenario. For east leading spade 9 probably from a doubleton gives you a viable path to take the finesse of the 10S from west thus enabling you to discard the heart loser. Alternately of course if you go for a ruff of the heart loser in dummy, then you can't finesse again in Trumps and your only hope would then be that east is saddled with Kx doubleton in trumps. The third alternate is also feasible if south decides to set up the club suit to take care of his spade and heart losers. But for that he would need to get his timing of the entries right and in proper order. Ruffing clubs would not allow a repeat trump finesse and taking the rather dubious finesse of the JC despite holding a doubleton club looks risky. For that the clubs need a favorable break as well as the lie of cards. Nor can he use the KC as an entry prematurely.
With all these options coming to mind, it is not easy to foresee the wining line, especially in the heat of the moment at the table. But a cool headed declarer who can reason with care to eliminate the lesser options would ultimately triumph in being able to reach the correct conclusion as to which line would succeed with the greatest chances of success.
As south how would you choose and why? For you see the opponents are never friendly and easy giving. The spade finesse option after the lead of the 9S from east looks tempting but cannot be a certainty for the simple reason that east's 9S, if not a singleton, needn't be a true card. For who would as east looking to the spade pips in dummy offer you this easy option. Suppose east is by leading from 109 deceptively. Then the contract would lose very early. Should the declarer then go for the second alternate and repeat the trump finesse, and for that should be access to the club king or go for the 8S in dummy?
Neither course was satisfactory as the cards lay. The expert declarer holding south's cards found a reasonably neat solution. He went confidently for the AD, felling east's doubleton KD as east's holding was:
10 9
A K 8 7 6 5 4
K 2
4 3
The vital question is why and how was south so confident of the KD dropping under the ace? Just think it over. If east had a third diamond, wouldn't he have killed the contract stone dead at trick 2 by leading his AH and forcing dummy to ruff to protect his KD from the repeat finesse. You will have to agree that the reasoning was simple.

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North

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A K 8 7

Q

5 4

K 9 8 7 6 5

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South

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J 6 3

3 2

A Q J 10 9 8

A 3

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The bidding proceeds:

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S     W      N      E

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1D    P     2C     2H

3D    P     3S      P

4C    P     4H      P

6D    All Pass

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