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Defensive problem

#1 User is offline   whereagles 

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Posted 2015-January-23, 05:44

MP, national sim.

Hope no one nags me for putting this on expert forum, but I really think this is expert stuff lol.



Just to clarify, the hand on the LEFT is DUMMY, and you're North, playing after it.

Pard leads a 4th best 4, taken in hand with the jack. Four rounds of diamonds follow, ending in dummy, after which declarer calls for a small heart.

1) What do you discard on the 3rd and 4th diamonds? After you make your 2nd discard, pard will disc the 6 (UDCA).
2) What do you play on the heart lead?
3) If you take the king, what do you play next?
4) Did you manage to do all that in tempo?
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#2 User is offline   mikeh 

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Posted 2015-January-23, 10:30

either it is too early in the morning (haven't had my coffee yet) or you have really fouled up the diagram. The diagram has East's hand visible yet the auction has E as the notrump bidder. It has N's hand visible and you say we are playing after East, which requires a reversal of the usual direction of play (a ploy not to be confused with a dummy reversal).

Anyway, I worked out the diagram eventually. If we are North, then the lower hand is Wes

Now I have my head wrapped around the diagram, I'll think about the problem.

Btw, making us do all this thinking up front might be enough, all in its own, to make this an expert problem :P

edit: I don't know what you mean about when partner makes his discard. Does declarer have 5 diamonds? The notion that partner discards 'after' we make our 2nd discard is ambiguous...since maybe the lead was from dummy.
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#3 User is offline   mikeh 

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Posted 2015-January-23, 11:04

Ok.

We know a remarkable amount about this hand at trick 1.

We can infer that declarer is 3=3=4=3 (I am assuming Nuno meant that partner pitched on the 4th diamond, not the 3rd...and at trick 1, we'd be placing declarer with 3=3=4=3 shape anyway)

While we won't know about the diamond J until it is played, the clubs are pretty safely marked as KJx.

So we can tentatively place declarer as either Axx Qxx Axxx KJx (where one diamond x may be the J) or Qxx Qxx Axxx KJx, and in both cases, declarer may have the major 10's and may have the heart J.

We won't have any future in hearts. He has 2 stoppers if we play them whatever his holding, assuming he has the Q.

Moreover, if he has QJx or Qxx there is no guess for him, so we can't do anything meaningful.

However, we can see at trick one that if he holds Axx Q10x Axxx KJx, then his best chance for a 10th trick, assuming he eschews an endplay, which would be both difficult and dangerous to play, since it requires establishing black winners for us, is to lead a low heart towards the Q10x and hope that we err or that he guesses well.

None of this is particularly difficult to work out at trick one, and this sort of thing is one reason to never play quickly to trick one even when declarer calls for a low club from dummy at the speed of light.

Once one gets to this stage, I think it is pretty easy to pitch a discouraging heart as one's first pitch and then a club.

Note partner cannot be quite as confident in his constructions. He gets the shape and the minors early, but the major honour location will be unclear, since he holds, probably, one spade honour and maybe one club honour. However, when we pitch a discouraging heart, he might consider not pitching one himself. Note that declarer will have a clue as the shape himself: if partner held a 4 card major, he'd almost certainly lead that rather than a club. On this auction, declarer will have 4 clubs a lot of the time, and leading from Q10xx or Qxxx is not a good idea if one has a plausible alternative.

Anyway, having defended this way, we play the heart 2 in tempo (if one can't play this in tempo, then we are pretty hopeless).

I think we survive even if he has Axx QJx AJxx KJx, because he can't strip the clubs and throw me in with a spade... the count isn't rectified.

and yes, after tanking at trick one, the rest would all be in tempo.
'one of the great markers of the advance of human kindness is the howls you will hear from the Men of God' Johann Hari
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#4 User is offline   ahydra 

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Posted 2015-January-23, 11:24

Very detailed analysis, but I have to wonder about how you deduced declarer's club holding. Surely partner would lead low from KQxx, declarer having AQx Q10x Axxx Jxx? I guess it doesn't make a lot of difference to the line though, as declarer would take the spade finesse.

ahydra
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#5 User is offline   whereagles 

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Posted 2015-January-23, 11:34

View Postmikeh, on 2015-January-23, 10:30, said:

Anyway, I worked out the diagram eventually. If we are North, then the lower hand is West. Now I have my head wrapped around the diagram, I'll think about the problem.
Btw, making us do all this thinking up front might be enough, all in its own, to make this an expert problem :P

edit: I don't know what you mean about when partner makes his discard. Does declarer have 5 diamonds? The notion that partner discards 'after' we make our 2nd discard is ambiguous...since maybe the lead was from dummy.


Damn I can never get this stupid diagram right for defense problems.. aaaargh. Yes, the hand on the bottom opened and is(was) dummy to 3NT. Don't ask me why the script printed it like that on screen LOL. And yes, declarer played AJ then small to dummy's K. Pard followed with Txx and discarded the heart in the Q.

EDIT: I think it's correct now.
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#6 User is offline   karlson 

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Posted 2015-January-23, 13:05

If we follow mikeh's analysis, but give declarer the ST, I think we need to hang on to both of our clubs (otherwise after heart to partner's jack, club exit and two rounds of hearts, we have to break spades without having established the long club).

I agree that the club position is not nearly as clear as mikeh makes it seem, but I don't really see a reasonable layout where we have to hop on the heart.
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#7 User is offline   mikeh 

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Posted 2015-January-23, 13:13

View Postahydra, on 2015-January-23, 11:24, said:

Very detailed analysis, but I have to wonder about how you deduced declarer's club holding. Surely partner would lead low from KQxx, declarer having AQx Q10x Axxx Jxx? I guess it doesn't make a lot of difference to the line though, as declarer would take the spade finesse.

ahydra

when one deduces the layout, this deduction comes with varying degrees of assurance.

I have assumed that declarer has KJx in clubs, but this is an assumption not cast in stone. However, and I didn't go into this detail in my analysis as written, because it was already lengthy, but it is a process I went through in considering the problem, IF declarer has J10x or Jxx, then firstly not everyone would bid 3N with that holding and, secondly, partner might, at mps, lead an honour (and almost surely would with KQ10x at mps), and, finally, take away the club K, and we are left at a minimum with AQx Qxx AJxx Jxx, and he will be playing quite differently. Admittedly, this difference won't be apparent until later, but he'd be incompetent to play as outlined with that holding. He can't test hearts before hooking spades, since if the spade hook loses, we clear clubs. And he doesn't have the entries to run the diamonds and then play spades. More normally, he'd hook the spade earlier, often very early.

So while Jxx or J10x are possible club holdings, they aren't imo likely club holdings.

When one has to make early decisions on imperfect information, then one needs to deduce the most likely layout and then commit to it. This sometimes leads to silly results, but as long as your thinking process is usually along the right lines, on balance your defence will be pretty good.
'one of the great markers of the advance of human kindness is the howls you will hear from the Men of God' Johann Hari
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#8 User is offline   cherdano 

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Posted 2015-January-23, 15:13

Surely declarer could have QJx? I don't see how he would play differently with Hxx QTx AJxx QJx.
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#9 User is offline   mikeh 

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Posted 2015-January-23, 15:47

View Postcherdano, on 2015-January-23, 15:13, said:

Surely declarer could have QJx? I don't see how he would play differently with Hxx QTx AJxx QJx.

of course he 'could' but the majority of players automatically win the Q with that holding. Again, as I mentioned earlier, when we need to infer holdings early, on limited information, it usually pays to infer the holding most consistent with the auction and the early play. Even if you are playing an opp capable of randomizing the card from QJx, which few would do (altho beginners tend to auto win with the J, but I am assuming non-beginners here), restricted choice suggests that is it more likely that the J was a forced card, as it would be from KJx, than from QJx.

And I do think that we are under some pressure to adopt a defence early on. Assuming partner has 4+ clubs, we know that declarer can run 4 diamonds at us and we therefore have to commit to our carding, especially if we want to create or leave doubt in declarer's mind.

And if partner holds K10xx in clubs, giving declarer say Axx Q10x AJxx QJx, then we still need to create an illusion in hearts. It does us no good to pop the heart K and clear the clubs, since declarer still gets the 9 tricks he always had. We duck, hope declarer goes wrong and that partner has the spade Q10x and finds the spade switch, ideally to the 10.

we can't cater to everything, so when one needs to commit early, don't worry about the lesser probabilities. And when one posts one's reasoning, unless one is a lot faster typist than I am one doesn't address every possible branch of the reasoning :D I mean, partner might have led from K654 as well, giving opener QJ10, but there is no point discussing that possibility separately than KJx.
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#10 User is offline   rhm 

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Posted 2015-January-24, 07:39

I am a simple soul.
Even at pairs if I can see a reasonable chance beating the contract I will go for it.
Partner's club lead is unusual from a four card suit after this bidding at pairs.
I doubt he would do it without the T. It marks both declarer as well as partner with 4333 distribution. Our chances beating this contract are much better if we assume the lead to be either from KTxx or Txxx
Declarer is marked with 8 tricks if he has the Q after the heart lead from dummy and he must have something in spades, which can not be the ace or he has 9 tricks now.
So give him QTx, QTx AJxx QJx. This gives partner Axx Jxx xxx KTxx from which he might well have led a club, since no other lead looks more attractive.
(After parter's heart discard declarer is unlikely to put in the T if you duck and declarer might not hold the T)
Why Mikeh thinks the majority would win the first trick with the Q escapes me. Partner did not discard a club which he would probably have done from QTxx in preference to a heart from Hxx.
Partner still has hopes getting his clubs developed, so he should hold KTxx
You must win and shoot back your remaining club.
If you duck the heart declarer will win and develop his ninth trick in spades.
You will either not get your heart trick or you will be unable to develop your club tricks in time.

An alternative is to play declarer for something like ATx JTx AJxx QJx.
Here ducking might get you 5 tricks, but declarer could guess right and whether partner would discard from Qxx seems dubious.
Another possibility I see is that partner has led from T654. But then he needs the Q and the ATx. Again you would have to duck the heart.

I discard a low card in each major and go in with the K.

Rainer Herrmann
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#11 User is offline   gwnn 

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Posted 2015-January-24, 07:51

View Postwhereagles, on 2015-January-23, 11:34, said:

Damn I can never get this stupid diagram right for defense problems.. aaaargh. Yes, the hand on the bottom opened and is(was) dummy to 3NT. Don't ask me why the script printed it like that on screen LOL. And yes, declarer played AJ then small to dummy's K. Pard followed with Txx and discarded the heart in the Q.

EDIT: I think it's correct now.

With defensive problems you have two nice ways of structuring the problem:

a) We are South, dummy is East or West.
b) Declarer is South, dummy is North.

Other formats invariably cause confusion. Anyway, I'm off to learn defence from mikeh and rhm. :)
... and I can prove it with my usual, flawless logic.
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#12 User is offline   gnasher 

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Posted 2015-January-24, 07:59

View Postrhm, on 2015-January-24, 07:39, said:

Partner did not discard a club which he would probably have done from QTxx in preference to a heart from Hxx.

Does partner know that declarer has only three clubs? I think that depends on what he thinks declarer would respond with a 2344 shape, and perhaps also on what he thinks I'd do over 1 with something like Kxxx Kxxxx xx 98.
... that would still not be conclusive proof, before someone wants to explain that to me as well as if I was a 5 year-old. - gwnn
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#13 User is offline   FrancesHinden 

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Posted 2015-January-24, 08:52

Surely partner will tell us about his club holding by his play in the diamond suit, whether we play smith or suit preference? Whatever signals we play, the order of partner's diamonds will mean something and it's odd not to be told what.
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#14 User is offline   whereagles 

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Posted 2015-January-24, 11:16

Partner's 1st diamond is count. 2nd and 3rd diamonds should be suit preference, but to be honest I never had a partner willing to bother with this subtlety (and believe me, I tried).

You'll have to assume 2nd and 3rd diamonds are neutral cards.
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#15 User is offline   whereagles 

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Posted 2015-January-26, 04:10

Thx all. Rainer got close, and I played like he said. But the actual layout was:


You'd need to be very inspired to find the killing spade switch, which is not clear to be percentage (nor is East's 3NT bid lol). I think this is a very difficult problem.

3NT was the contract at just about every of the 30 tables in play. It went down a couple of times when it was played by West, on the obvious spade lead by North. Only two tables set it on a South lead.
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#16 User is offline   cherdano 

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Posted 2015-January-26, 05:03

View Postwhereagles, on 2015-January-26, 04:10, said:

I think this is a very difficult problem.

I would suggest that the problem could have been made slightly easier by adopting normal "Expert-Class Bridge" defensive signalling methods.

But even if you don't play useful defensive (giving any count signals on this hand after declarer shows 4 diamonds is, well, hard to understand) partner could have clarified the club situation by, well, pitching the T.
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#17 User is offline   whereagles 

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Posted 2015-January-26, 05:40

Yes, discarding the club 10 is probably the best way to make it clear.
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