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Beautiful double dummy problem

#1 User is offline   cherdano 

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Posted 2015-February-21, 15:32



3NT by North. Play or defend?


P.S.: This hand came up in the BBF vs JEC match today. Not sure I have ever encountered such a beautiful double dummy problem outside a bridge book.
The easiest way to count losers is to line up the people who talk about loser count, and count them. -Kieran Dyke
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#2 User is offline   Phil 

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Posted 2015-February-21, 17:22

Great hand. I think I defend and lead a low heart.
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#3 User is offline   wanoff 

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Posted 2015-February-21, 18:02

Best lead is a heart but I think it makes since W is squeezed on the last diamond.
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#4 User is offline   cherdano 

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Posted 2015-February-21, 18:16

To paraphrase another poster, I am pretty sure neither phil nor wanoff deserve full credit at this point. There is more than one variation to consider...
P.S.: It might be most interesting on a heart lead, ducked, heart continuation.
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#5 User is offline   Cyberyeti 

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Posted 2015-February-21, 18:16

View Postwanoff, on 2015-February-21, 18:02, said:

Best lead is a heart but I think it makes since W is squeezed on the last diamond.


It's more complicated than that, it looks like dummy might have to make an embarrassing discard on the third heart at some point, but unfortunately E has to make an equally embarrassing discard first.
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#6 User is offline   Fluffy 

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Posted 2015-February-22, 05:40




If this position is reached I think declarer has no way to make.
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#7 User is offline   wanoff 

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Posted 2015-February-22, 07:22

View PostFluffy, on 2015-February-22, 05:40, said:


If this position is reached I think declarer has no way to make.


Exactly, so you wouldn't duck the heart. Alternatively E or W could keep a heart instead as the exit card.
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#8 User is offline   helene_t 

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Posted 2015-February-22, 07:29

I looks like there is a squeeze but I don't see it. Say we duck the lead and play diamonds, discarding for example a spade. In the six card ending, if W keeps A QJ A72 and East keeps K5 5 J96, how can declarer make?
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#9 User is offline   wanoff 

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Posted 2015-February-22, 07:52

ok I've changed my mind. If W avoids the squeeze and chucks three high hearts, E can squeeze dummy with 8.
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#10 User is offline   sathyab 

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Posted 2015-February-22, 16:47

Arend and I were at the table when this hand came up. It was so interesting, that I saved the hand to analyze it a teaching table later. Quite a few variations are truly double-dummy. If declarer doesn't follow the exact sequence of plays, defense can prevail, but single-dummy, defense finds it hard to exploit it. But there're some useful single-dummy angles too. For EW this feels like a chess problem "mate in 13 moves" :)

Declarer starts off by ducking the first . Takes the second one, one high from hand and another to end in dummy. Now play the remaining high from dummy. discard by West is fatal double-dummy as we can see, but even single-dummy, West has to hope that partner has one useful card, the K, as a card doesn't help directly. So let's say he pitches a , East can spare a black card easily. On the next , West can't still afford a , but if he blanks his A, it's over for the defense. Declarer plays a to the Q, cashes one more . West still can't afford a discard, so a now. Declarer cashes high and tucks West in with a for a end-play.

So West's second pitch is a . Defense hasn't given up on the hand yet, they can still get 2, 2 and a . Now declarer plays a to Q, cashes the last . West can not blank either of his black Aces, so has to pitch a . After 5, two and a , remaining cards are: West Ax Q - Ax. East in the meanwhile is down to Kxx - - J9 and dummy is QTx - - Kx. Now declarer cashes high , East is forced to pitch a , as does dummy. Declarer exits a and whoever wins the last is end-played to give declarer the game-going trick in .

Single-dummy, should declarer give up on the finesse for J ? Not clear. If he did, he could go down in the five card ending above when it was makeable.
Seeking input from anyone who doesn't frequently "wtp", "Lol" or post to merely "Agree with ..."
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#11 User is offline   cherdano 

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Posted 2015-February-22, 17:08

See also http://bridgewinners...-dummy-problem/
(And thanks to Sathya for the discussion!)
The easiest way to count losers is to line up the people who talk about loser count, and count them. -Kieran Dyke
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#12 User is offline   nige1 

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Posted 2015-February-22, 17:15

View Postcherdano, on 2015-February-21, 15:32, said:


3NT by North. Play or defend?
P.S.: This hand came up in the BBF vs JEC match today. Not sure I have ever encountered such a beautiful double dummy problem outside a bridge book.
Great problem, Cherdano. Deep finesse says you can succeed by winning a lead with K and cashing JQKA.
  • If LHO discards a black card, then you lead a . But
  • if LHO throws 2 s, then you play on the majors.
This avoids you end-playing yourself as in Fluffy's putative ending.

Simplified version with West on lead. At trick 1, East wins K and leads a second , forcing declarer to play for cherdano's pretty over taking squeeze.

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#13 User is offline   helene_t 

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Posted 2015-February-23, 10:42

View Posthelene_t, on 2015-February-22, 07:29, said:

I looks like there is a squeeze but I don't see it. Say we duck the lead and play diamonds, discarding for example a spade. In the six card ending, if W keeps A QJ A72 and East keeps K5 5 J96, how can declarer make?

Of course, cash the K before exiting with a spade. West can take his hearts but East's spade trick is gone and the club suit is frozen.

But W doesn't neet to keep three clubs afaics. So I would think declarer has to start, before playing out all the diamonds, by playing a low club to the queen. Now West can't afford to bare A.

Without seeing the EW hands, the squeeze must have better chances of making DD than the finesse when one takes into consideration that the bidding suggests that W has come points. Even if East has A so your Q loses, you can still squeeze W if he has J and at least one club honour. A hero E may duck the first club trick, maybe.
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#14 User is offline   inquiry 

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Posted 2015-February-23, 15:13

View Posthelene_t, on 2015-February-23, 10:42, said:

..... when one takes into consideration that the bidding suggests that W has come points. Even if East has A so your Q loses, you can still squeeze W if he has J and at least one club honour. .....



Did I miss something, why do we assume West has some points. The only bidding given was 3NT (I don't believe for a second the opening bid was 3NT),,,, what was the bidding?
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#15 User is offline   helene_t 

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Posted 2015-February-23, 16:59

View Postinquiry, on 2015-February-23, 15:13, said:

Did I miss something, why do we assume West has some points. The only bidding given was 3NT (I don't believe for a second the opening bid was 3NT),,,, what was the bidding?

At our table et went (south opened)
1*-1-1**-2
pass-pass-3NT

1=polish
1=transfer to nt (2 would have been nfb)
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#16 User is offline   helene_t 

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Posted 2015-February-24, 17:35

Suppose declarer ducks the lead, wins trick two, plays a low club to the Q and plays the diamonds. In the five card ending:
- W bares A: cash K and throw W in with a spade.
- W bares A: exit a club, Q will be the 9nth trick (they can refuse to give us K but in that case dummy gets a spade trick)
- W keeps only one heart: Play K and dummy keeps black suit parity with East. Now exit spade, opps will have to bring us a club trick.

But what if W keeps three spades?

If we play K, dummy has to discard before West.
If we exit with a spade, East will take, return a heart, again squeezing the dummy.

So it seems to me that we must not duck the opening lead. Then we keep the small heart as a menace, forcing at least one opp to keep a heart parity.

Is that right?
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#17 User is offline   cherdano 

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Posted 2015-February-24, 18:31

View Posthelene_t, on 2015-February-24, 17:35, said:

Is that right?


It is right that if declarer ducks the opening lead, and leads a club to the queen early, then West can beat him. But he can still make after ducking the opening lead...
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#18 User is offline   alok c 

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Posted 2015-February-25, 08:41

View Postcherdano, on 2015-February-24, 18:31, said:

It is right that if declarer ducks the opening lead, and leads a club to the queen early, then West can beat him. But he can still make after ducking the opening lead...

cash heart a come tohand via diamond lead club to q then cash four diamonds ending in six cards.west has to preserve two each in black suits.now exit with a spade.
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#19 User is offline   Free 

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Posted 2015-February-25, 09:15

View Posthelene_t, on 2015-February-24, 17:35, said:

So it seems to me that we must not duck the opening lead. Then we keep the small heart as a menace, forcing at least one opp to keep a heart parity.

Is that right?

I don't think so. There are various lines of play depending on what West does. That's why you need to run AKQJ first: you'll see what LHO discards after which you can anticipate. Ducking or not doesn't make much difference, because you can duck a later.

After ducking the 1st trick there is 1 constant: you have to play a to the Q at some point. But you can't do it too quickly, because you need the Q as an entry for the 5th !
1. If he discards at least 1 , you can play a to the Q and score 2 tricks.
2. If he keeps his s and discards s instead, you can play to the Q, K and endplay W
3. If he keeps his s and discards s only, you can play to the Q and develop a trick in s (s are blocked and reds are eliminated)
4. If he keeps his s and discards 1 and 1 , you play to the Q and your last giving West a dilemma: discard means you can develop a (like in 2), discard means he'll get endplayed (like in 3)

The point of this hand is that neither West nor East can discard s as long as we have a top .
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#20 User is offline   cherdano 

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Posted 2015-February-25, 11:49

View PostFree, on 2015-February-25, 09:15, said:

After ducking the 1st trick there is 1 constant: you have to play a to the Q at some point. But you can't do it too quickly, because you need the Q as an entry for the 5th !

That's not true. If you always plan to play a club to the Q, then West can beat you by pitching hearts only, for the reasons explained by Fluffy. In any case, I think the solution is explained fairly comprehensively in the post on bridgewinners (linked above).
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