Bridge is a game essentially of foresight. For it begins and ends keeping the bid contract in sight, trying to find all roads leading to Rome. A good declarer never loses sigh of the ultimate aim and that is to bring the bid contract successfully home. Of course, the bidding by the opponents and their overall approach in defense besides the opening lead are vital clues that can led a skilful declarer of vision and foresight pick the winning line out of nowhere as did Bob Rowlands in an English Championship of team of four played way back in 1979 at London.
Let us give you the north-south hands and the bidding placing you in the south seat held by Rowlands in that memorable championship where the bidding proceeded as under after the N-S deal given:
The opening lead was the AS led by west, east following with the deuce west now wisely switched to the 2H. Take it from there. As south, how do you proceed to make this dubious contract doubled by east?
First, as usual, let us analyse our prospects in the light of winners and losers, always keeping the 11 trick contract bid in sight. Already a trick has been lost to the opponents in the shape of the opening lead of the AS. Of course one thing is certain. If the diamonds stacked with east in lieu of his double need to be picked up, being 4 in number headed by the K10, dummy would have to lead twice in diamonds there being two entries in it with AH and the K of clubs. But then how would the clubs he played for a one loser? Would a simple finesse of JC do? Let us again pick our clues from the bidding. West has bid 4S on his own after opening with 1S and he is almost certain to have a void in diamonds.
He has also indicated by his switch to 2H on his second turn to be holding 4 hearts. Well if we give east at the most 3 spades, that would leave west with 7 spades and 4 hearts and a doubleton club. Of course we can't be certain of east holding 3 spades looking to his 1NT bid on partner's, 1S. With 3 spades, he could will bid 2S. So the likely presumption and one which is more logical is to give east a doubleton spade which in turn would mean west holding a singleton club with a 4-1 club break, to play the clubs only once from dummy in lieu of the short age of entries in dummy with the 2 needed for picking the 4 card diamond suit of east. Rowlands realised he needed an extra entry to dummy. Of course all would be well if west's presumed singleton was an honour - either QC or 10C for then the clubs could be picked up in no time. But the vital challenge posed was: what if west's singleton was not an honour? Rowlands then had to visualise the only possible distribution that would give him a ray of hope. And that is to presume west either to hold a QC, or a 10C, failing which at least a 7C.
This is where the dividing line between experts and ordinary players in bridge is marked out. The expert would look for the only chance, which most players of lower category would certainly overlook. Can you spot why this presumption of west holding at least 7C is so important? Yes - because then dummy's 6C could well become a vital entry, provided of course if the declarer was wise enough to unblock the bigger clubs from hand - a prerequisite blocking play to create the essential entry required. To cater to this, look how beautifully Rowlands managed, his doubled contract. After 9D finessed successfully followed by 8D covered by the 10D and JD, to confirm spade distribution declarer cashed the KS seeing east's JS dropping. Now he led 9C and ran it to east's 10C. As expected west's 7C singled out. Ruffing the heart return, he led the 8C to dummy's ace and continued with JC.
This was the end for east. If he played low. Rowlands would remain in dummy to take the further diamond finesse needed. If on the other hand east covered with QC, Rowlands would mother it with AC and get back to dummy by overtaking 4C with the carefully earned 6C entry in dummy to take the diamond finesse and bring the contract home. It was all foresight - the unblocking of clubs, leading all roads to Rome.

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North           South
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    7              KQ
A9753              10
  984          AQJ765
 KJ62            A984
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 W       N       E       S
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1S    Pass     1NT      3D
4S      5D     Db1
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