Zero Defense

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    The Zero Defenseby Kit Woolsey, Arlington, Va.W hen a defender has a prob-

    lem, he should attempt to constructvarious hands declarer might haveconsistent with the bidding and play.The defender then chooses a defensenecessary to defeat the contract ifdeclarer has one of these hands. Ifdeclarer's hand is different, and adifferent defense would have beensuccessful, the defender was unlucky;or perhaps he showed bad judgment inestimating declarer's likely hand. Buthe did not make a technical error,provided that the winning defensewould have been unsuccessful on thehand he mentally constructed.

    In contrast, a defense that is notnecessary against the imagined holdingis an error. A defender may decide toplay declarer for holding X, on which aspade shift is successful, but if adiamond shift not only defeats holdingX but also defeats holding Y , while aspade shift does not, then the spade shiftis what I call a "zero defense": adefensive play that can never be correct(even though it might succeed), becausean alternative play is as good or betteragainst all declarer's possible holdings.This type of error seems easy to avoid,but it is actually quite common. Toooften, a defender jumps at the first handhe constructs, without fully consideringalternative hands and defenses. Forexample,

    NORTH i dummv) K .\;:J862o 8 7 5 3"" Q J 10 3WEST (vou).98'653v A Q 7 4OAK 6

    "" 5WEST NORTH SOUTHI .PassEASTPassD'ble I NTPass PassPassOpening lead: 0 KYou lead the king of diamonds, and

    partner produces the queen. What now?A low heart shift could be right ifdeclarer holds,.AQJIOxx vxxx Ox ,,"AKx,although this wouldn't say much foreither declarer's bidding or partner'ssignal at trick one. But a low diamondcontinuation, playing declarer for, AQJ 10xx v Kx 0 xx "" AKx,is a zero defense. If declarer has thathand, a club shift will also suffice, anda club shift is necessary if declarerholds, AQJ 10xxx v x 0 x x "" AKx,(his actual hand in real life). This mayseem simple, but it was missed at bothtables in a Grand National Zonals.

    Try your hand at these IMP prob-lems. Assume reasonably competent

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    opponents, whose bidding and play atleast border on sanity. There mayormay not be a clearly correct answer, butmake sure that you avoid any zerodefense.(I)

    NORTH (dummy) Q J 9'V K 7 2o J 84ofoA743

    WEST (vou) K 854'V Q 10 3o 962o f o K J 6WEST NORTH EAST SOUTH

    1 NT*Pass 2 NT Pass 3 NTPass Pass Pass*13-15

    Opening lead: 4Dummy's queen of spades holds.Declarer leads a diamond to his queen,

    partner playing the three, and continueswith a low spade towards dummy. Yougrab your king, and partner's ten comestumbling down. Now what? A heart orclub shift, looking for gold in partner'shand, both seem reasonable; so does apassive spade return. Or do they?(2) NORTH (dummy) J 94

    'VA87652o K J 9ofo 3

    WEST (you) A 106'VQJ93o Q 4ofo 10 9 7 4WEST NORTH EAST SOUTH1 NT

    Pass 2 'V(All Pass)PassPass 2 0*4 'V*transfer

    Opening lead: o T e 10

    Your club lead rides to declarer'sking. He plays three rounds of hearts toyou, partner following once and thenpitching two clubs, while declarerpitches a diamond. Naturally, you exitsafely with a club. Declarer pitches adiamond from dummy as he wins hisace of clubs. Then he tries king ofdiamonds, ace of diamonds, and adiamond. You are out of diamonds, soyou have to do something. Does itmatter?(3 )

    NORTH (dummy) Q 7'VQJ42o K Q 1094ofo A 6

    WEST (you) 8642'V K 6 3o 72ofo J 10 9 4WEST NORTH EAST

    1 0 PassPass 2 0 PassPass 3 'V PassPass Pass Pass

    SOUTHI .3 03 NTOpening lead: o T e JYour club lead goes to partner's king,

    and he returns the two of clubs todummy's ace. Declarer plays a smallheart: nine, ten, and king. What now?Do you press the club attack, fire heartsback at declarer, or break new ground inthe spade suit?

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    (4) NORTH (dummy) A K 5 4'V 10872o A J... A Q 3 EAST (you)

    Q 8 2'V K J 4o Q 9 5... K 7 6 2WEST NORTH

    I ...3 Pass

    EASTPassPassPass

    SOUTHI ..assPassOpening lead: o T e JDeclarer goes up ace of clubs, cashes

    ace of spades (partner showing out),ruffs a club, then plays a spade to theking, ruffs a club, and puts you in witha spade. Partner has pitched two clubsand a diamond on the spades. You havethree ways to get out. Which do youtake (or not take)?(5) NORTH (dummy).AJI03'VQJ1054c J 642

    . . . -WEST (you) 86'V A 8 6o A 5",J109842WEST NORTH EAST SOUTH

    I 0I .assPass I'V4 . Pass(All Pass)Opening lead: o T e JDeclarer ruffs the opening lead, plays

    a heart to the king, which you duck(partner playing the two), and continueshearts-you win. What a mess! Thereseems to be something to be said for andagainst all four suits. Ace and adiamond wins outright if partner hasking-third, but could well blow the hand

    if he doesn't. A club continuation,pumping dummy, could work, butdeclarer might discard and set up a keytrick for his king of clubs. A trump shiftcuts down dummy's ruffing power, butmight pick up partner's queen. A heartcontinuation is safe enough, but mightcost a critical tempo. Can you showsome of these arguments to be fallaci-ous?

    ANSWERS

    (1) NORTH Q J 9'V K 7 2o J 8 4... A 7 4 3

    WEST K 8 5 4'VQ103o 962... K J 6

    EAST 10 6'VA984o 1073... Q 9 5 2

    SOUTH A 7 3 2'V J 6 5o A K Q 5... 10 8A club shift might be essential if

    declarer has, say, Ax x x 'V AJx 0 KQ lOx ... x x ,but it might also give declarer his ninthtrick when he has the queen of clubs. Aheart shift, however, is definitelywrong. If declarer has, Ax x x 'V xxx 0 AKQx ... Qx,a passive spade return will also beat thecontract, as it does on the actual deal.Declarer would not have opened onenotrump with a concentrated 5-4 in thepointed suits, so the spade return winswhenever the heart shift does, as well ason hands on which the heart shift loses.That makes the heart shift the zerodefense.

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    (2) NORTH J 9 4'VA87652o K J 9. 3WEST A 106'VQJ93o Q 4.10974 EAST K 8 5 3'V 4o 52.QJ8652SOUTH Q 72'VKIOo A 1087 6 3 A KA tricky problem-you had better

    discard a trump! Then, after you exitwith a club, the set is 100 % secure(declarer can hardly have ace-king-queen of clubs and no king of spades, ashis line of play would then be lunacy).Since ruffing guarantees a set whilediscarding risks the actual hand, anyother play is a zero defense. Did youfall for this swindle? West did at thetable, as did many experts (includingthis writer) when given the problem.(3) NORTH

    Q 7'VQJ42o K Q 1094 A 6WEST

    8642'V K 6 3c 72.J1094EAST K J 10'VA987o 85 K 7 5 2

    SOUTH A 9 5 3'V 10 5o A J 6 3 Q 8 3

    Partner needs to have a red ace,probably the ace of hearts, for thedefense to have a chance. After declarerknocks that ace out, he will have ninetricks if he has the ace of spades, or beready to set up his ninth trick if he has

    the spade king. So, a heart return isclearly inferior to a club continuation. Aspade shift is essential if partner holdsking-jack-ten, irrelevant if he holdsace-jack-ten, and disastrous if he holdsace-jack-small, so it looks as thougheither black suit could be right.However, with, K 10xx 'V lOx 0 AJxx Qxx,declarer would surely have gone afterspades, not hearts, for his ninth trick.Consequently, the spade shift willalways set the hand if it is beatable,assuming a rational line of play bydeclarer. So, the club continuation isalso a zero defense.( 4 ) NORTH

    A K 5 4'V 10872o A J A Q 3WEST. -V A 9 5c 10 8 6 3 2 J 10984 EAST Q 8 2'V K J 4o Q 9 5 K 7 6 2SOUTH J 109763'V Q 6 3o K 7 4 5A club loses if declarer has,

    J 109xxx 'V Axx 0 xxx x .A heart loses on the actual deal. And adiamond loses if declarer has, J 109xxx 'V Ax 010xxx x ,In each case the other two exits aresuccessful, so it looks like a guess. Waita minute! If declarer had four diamondshe would scarcely have played this way;he would have arranged to ruff twodiamonds in dummy. Any time declarerhas three diamonds, the diamond shiftcan't cost a trick. So the diamond exitsucceeds whenever the hand is beatable,and anything else is zero defense.

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    NORTH A J 1 03\? Q J 1 0 5 4o J 642oTo -

    WEST EAST 86 .952\?A86 \?972o A 5 0 Q 109oTo J 1 0 9 8 4 2 oTo A Q 7 5

    SOUTH K Q 7 4\? K 3o K 8 7 3oToK63

    (5)

    This is a fairly complicated hand.Let's look first at the diamond shift.This pretty much needs partner to haveking-third to be successful. And if hehas this holding a club continuation willalso suffice-declarer will eventuallylose control. He can't have, KQx x \? K x 0 Q 10x x oToAx x ,or he would have won the first trickwith the ace of clubs, drawn trumps,and gone after hearts. Therefore, thediamond shift is a zero defense.

    The club continuation will probablylose on the actual hand, since declarer ispretty much forced to discard; and then

    he needs only to guess the diamondsright if partner switches. In contrast, ona major-suit shift declarer would proba-bly draw trumps, run the hearts, andlead a diamond to his king. Down one .

    However, if declarer has, say, KQx x \? K x 0 Q IOx x oToKx x ,a major-suit play allows him to makethe hand. (He draws two rounds oftrumps, starts running hearts, overruffspartner, and then goes after diamonds.)Here, a club continuation forces him tolose control.

    In choosing between major-suitshifts, there is no reason to prefertrumps, as declarer is not reallycross-ruffing. And a trump shift couldcost, if declarer has, say, K9x x \? Kx 0 K 10x x oToKx x .So the trump shift cannot be right-theheart continuation is always at least asgood. If you chose either a club or aheart for the right reasons, you havemade a reasonable play, even if it turnsout wrong. But if you played a spade ora diamond you have found a zerodefense, regardless of the final result.