Bridge is a battle of wits between the declarer and the defenders. Like a see-saw, the balance swings to and fro as each stroke of the declarer is countered by an equally brilliant stroke of defence, quashing any advantage declarer hopes to gain. In this battle to outwit each other, sometimes the defence slips, while at other times the declarer mucks up.
In bridge, success rests on seizing the opportunity given by either side. Those who hold on to their nerves and make fewer mistakes are bound to be victors, like in the following hand. In a major tournament in the US, south found himself in a 4S contract that was on the face of it not too complex a hand a work out. The opening lead was a diamond.
As south, how do you foresee your chances of making 4S? Obviously, you have a club loser, a probable heart loser or even two heart losers if KH misguessed and the spade loser staring if the finesse fails. The question still remains: the heart situation is too fragile. For howsoever right a guess you make in hearts, ultimately you would be losing 2 hearts, even after winning KH. Thus with KS offside, this contract of 4S cannot be made unless the declarer can manages to get his diamonds running.
Sometimes a bridge contract rests on how the cards behave; on other times on how you play or defend. But invariably it rests on your timing of the play which is of the essence of good dummy play. For in it lies the key to the required entries for the contract to come home.
While several alternatives are always available to the declarer to choose his best line of play which would in his opinion, be the winning play, the declarer in the present context in actual play thought it best to knock out as many trumps as possible in the quickest possible manner as he was willing to give up spade, a club and a heart, holding on to his diamonds with the sure KH as the entry to his dummy. With this plan in mind, after winning the DA, the declarer cashed the spade ace and played a spade to the KS that west held.
Following the actual play, west holding the tenuous AQ clubs and looking to dummy's massive diamonds, was mortally afraid that the club tricks were bound to disappear in case he did not cash them now. So he went for them - and kaput it was curtains for the defence. Declarer ruffed the second club, knocked the last trump out, and ran his diamond winners.
As you must have realised by now, both sides had mucked up. First, it was the declarer, and then the defender. Can you spot how? Let us work out the solutions of both.
The declarer was under an illusion that his losers were restricted to only 3 - one in each suit, except diamonds. What he did not realise was the brittle entry position of diamonds in dummy which brings us to how the defence failed to encash the opportunity given by the declarer in his ice-cold contract when he played the AS and another to the KS.
At this point of time, the defence got a little carried away by illusory fears that the club tricks were running away in the massive diamond holding of dummy. But that was just an illusion. All the defence had to do was cut off dummy's vital entry to those diamonds by playing the AH and another heart to KH in dummy. This would be the scissor's, nip. The declarer would be cut from the dummy, with no way of enjoying the diamonds as he had no way to enter his hand for knocking out east's last remaining trump. The declarer's attempt at clubs would obviously fail as west would take the club and cash his QH for the setting trick.
It was really a matter of simple defence that west had mucked up and thereby lost the opportunity so erroneously given to him by the declarer who by the way could have assured the contract of 4S by a very simple device which would always keep him in control of the situation. Can you see it now? Yes, by simply leading a small spade to the QS in the first place and the defence is over.

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North     West     East     South
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QJ          K2      754   A109863
K9       AQ865       32     J1075
KQJ1064    975       83        A2
1073       AQ2   KJ9654         8
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