I have forgotten which battlefield tactician counseled that the best defense was to attack, but in contract bridge the advice is not always valid. The best defense does not necessarily begin with an attacking lead. In pair tournaments scored at match points it is especially important not to give up an extra trick with the opening play, and it is here that there exists the widest gulf between rubber bridge and duplicate competition.
At the same time there is no question about whether defense or declarer's play is more important. Most bridge pair tournaments are decided by good opening leads and tight defense, if only for the reason that if the cards run about even and your side wins its due share of the contracts you spend about 25% of your time sitting on the sidelines as dummy. And then only your exceptional talent as bidder receives its just reward. On that 50% of all deals where the opponents buy the contract, however, you, as a defender, are in the action all the time, with hopes of gaining some reward for your playing talent as well.
Suppose you were holding the West hand shown here. You are allowed to look at your cards and North's but cover the East and South hands to see whether you can equal the defense of Jan Barna, who, as West, brought off a brilliant coup that set the three-no-trump contract at the recent Canadian-American tournament in Montreal.
Most experts would lead the heart as Barna did, in spite of North's bid of that suit. The solidity of the heart holding insures that no trick will be given away by the opening that declarer could not make on his own account. The play to the first trick gave West the opportunity to see that the opponents had four sure tricks in the heart suit, since declarer won the trick with the king in his hand in order to lead the jack of spades. You may now take over for West and plan how you can defeat South's contract.
First of all, South has apparently made a poor play by leading the spade jack. With dummy's holding in the suit, declarer should have led a low spade, leaving West in doubt as to whether South was planning to finesse for a possibly missing jack of spades. By leading the jack, South has given West a present of the information that East does not hold that card. West's problem is to make the utmost use of that information.
After considerable thought, Barna came to the conclusion that his best chance to defeat the contract was to find partner with the king of spades and either the 10 or 9 of clubs as well. East needed only one, not both, of those lower cards.
Defying the time-honored secondhand-low precept, and also committing the "folly" of leading queen from ace-queen without a supporting honor, Barna climbed up with his ace on the first spade and returned the queen of clubs. That smothered dummy's jack and presented South with a trick which, nevertheless, had to cost him his contract.
If for some reason South ducked the trick, West could continue with a low club and win two more club tricks whenever East got in with the king of spades. Even if declarer had been gifted with second sight in the division of the diamonds, he could not take advantage of the fact that, if he went to dummy with a heart and finessed the diamond queen on the first round, West's blank jack would drop. Since he could not get back to dummy again without surrendering a spade or a diamond trick, there would be no way to make four tricks in the suit.
What actually happened was that South took West's queen of clubs with his king at the third trick and continued spades. East won with the king, shifted to the 10 of clubs and the defense collected two spades and three clubs to set the contract.
A final note on West's play to the first spade trick: if he allowed his partner to win that trick with the king, the contract could not be defeated, even if East then shifted to clubs.