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Play 6C

#1 User is offline   broze 

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Posted 2014-March-10, 03:20



Lead T

Is there a clear best line here? Good opps playing standard carding.

Comments on the bidding welcome.
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#2 User is offline   helene_t 

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Posted 2014-March-10, 03:53

I will win in my hand and play a heart. If LHO has A I am home. Assuming that RHO wins and return a diamond, I am hoping for clubs 2-2 and J coming down. Or 7 singleton with the short hearts. So when I cross to dummy for the second time I overtake 8 with the 9.
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#3 User is offline   broze 

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Posted 2014-March-10, 04:00

View Posthelene_t, on 2014-March-10, 03:53, said:

I will win in my hand and play a heart. If LHO has A I am home. Assuming that RHO wins and return a diamond, I am hoping for clubs 2-2 and J coming down. Or 7 singleton with the short hearts. So when I cross to dummy for the second time I overtake 8 with the 9.


If you know LHO has the A you are home but if you lead to the K and it holds either opponent could be ducking.
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#4 User is offline   whereagles 

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Posted 2014-March-10, 10:13

If they duck the heart (hats off to them), just play for some sort of throw-in squeeze, hoping to find the K together with A. Ruff two diamonds, run the club, watch discards and guess the endplay.

This is the easy way out. You can also try and keep the diamonds intact and play for some crazy compound throw-in ruffing squeeze (the kind that happens once in a lifetime).
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#5 User is offline   broze 

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Posted 2014-March-11, 07:32

View Postwhereagles, on 2014-March-10, 10:13, said:

If they duck the heart (hats off to them), just play for some sort of throw-in squeeze, hoping to find the K together with A. Ruff two diamonds, run the club, watch discards and guess the endplay.

This is the easy way out. You can also try and keep the diamonds intact and play for some crazy compound throw-in ruffing squeeze (the kind that happens once in a lifetime).


It seems pretty easy to duck the heart Ace though, no? Doesn't seem like it can cost much to me and it is even easier if LHO was given count on the first diamond trick. RHO will find it trivial to duck if he can get clear count in that suit.

I can't see what squeeze lines you are suggesting. But whatever they are they surely don't beat just finding the A onside. This was not a clear problem for me.
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#6 User is offline   jmcilkley 

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Posted 2014-March-11, 07:36

View Postbroze, on 2014-March-10, 03:20, said:



Lead T

Is there a clear best line here? Good opps playing standard carding.

Comments on the bidding welcome.


seems to me that the only chance is to find A or J hearts with W and be able to dump a losing spade on a heart. So I would first play towards KQ and if A comes from W then I have no problem anyway. If not I play K and if taken by A then next time I have to finesse 10
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#7 User is offline   brettnj 

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Posted 2014-March-11, 08:09

Play should be routine. cash A-c at trick 2, and lead a
heart up. Assuming RHO wins, and returns a D, win in dummy,
ruff a d high, cash A-S (i.e., possible Vienna Coup, which is
more probable that a one-entry criss-cross squeeze, and run
the clubs --- there are many double squeeze chances. If the K-s doesn't show, and a high diamond remains, if all else fails, you can finesse the 10-h.
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#8 User is offline   broze 

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Posted 2014-March-11, 09:47

View Postbrettnj, on 2014-March-11, 08:09, said:

Play should be routine. cash A-c at trick 2, and lead a
heart up. Assuming RHO wins, and returns a D, win in dummy,
ruff a d high, cash A-S (i.e., possible Vienna Coup, which is
more probable that a one-entry criss-cross squeeze, and run
the clubs --- there are many double squeeze chances. If the K-s doesn't show, and a high diamond remains, if all else fails, you can finesse the 10-h.


It's hardly routine to play for squeezes that can't materialise. With all the threats in dummy any relevant squeeze would need the heart jack onside anyway, wouldn't it? Unless I am missing something. I can't picture a possible double squeeze.

EDIT: Although I suppose you have a show-up squeeze if RHO wins the first H with AJ doubleton and LHO has the SK.

Anyway, like I said, the opps can get count of the hand pretty quickly and the first heart you play to dummy can be ducked by either opponent. If you play another heart to dummy later and that is ducked as well it looks to me that you are on a guess.
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#9 User is offline   JLOGIC 

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Posted 2014-March-11, 11:04

View Postbroze, on 2014-March-11, 09:47, said:

Anyway, like I said, the opps can get count of the hand pretty quickly and the first heart you play to dummy can be ducked by either opponent. If you play another heart to dummy later and that is ducked as well it looks to me that you are on a guess.


Technically it's not an equal guess, it is better to play a heart to the king and a heart to the queen whether RHO wins the ace or not. Of course in real life you can choose to use your judgement if you have some kind of read who has the ace.
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#10 User is offline   whereagles 

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Posted 2014-March-11, 11:15

View Postbroze, on 2014-March-11, 07:32, said:

I can't see what squeeze lines you are suggesting.


If someone is brazen enough to duck the heart and he happens to have the spade king as well, you might make him pay back with interest if cards lay like this (East still to discard)



Of course, you'll still have to read the position and decide which card East bared. This works symmetrically between E/W but there's some guesswork involved. So yeah, a simple "two hearts up" may be preferable.
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#11 User is offline   WellSpyder 

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Posted 2014-March-11, 11:18

View PostJLOGIC, on 2014-March-11, 11:04, said:

Technically it's not an equal guess, it is better to play a heart to the king and a heart to the queen whether RHO wins the ace or not.

Is that right? I can see the reasoning for that if you need to establish the suit for one loser (you pick up Jx offside, while playing to 10 on the second round doesn't set up the suit if RHO has Ax). But here you only need to establish a second winner, not the whole suit, so I'm not sure that argument applies.
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#12 User is offline   JLOGIC 

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Posted 2014-March-12, 10:23

View PostWellSpyder, on 2014-March-11, 11:18, said:

Is that right? I can see the reasoning for that if you need to establish the suit for one loser (you pick up Jx offside, while playing to 10 on the second round doesn't set up the suit if RHO has Ax). But here you only need to establish a second winner, not the whole suit, so I'm not sure that argument applies.


Yeah it is. It is counter intuitive, but if you think about it this way, I think it will make sense:

My strategy is to lose to the ace offside, and pick up the ace onside plus AJ doubleton offside. Regardless of what they do with Ax(x) (ducking or winning at any frequency), I will pick up those combos. Any other strategy is exploitable by their play with Ax(x). No strategy does better unless you are exploiting them (for instance, bad players typically win the ace on your right with the ace often enough that in real life we always play low to the ten next after they do that), but if you are trying to exploit them you may be exploited.

Ofc if you have any kind of read on the table action/tempo/english they play their cards with whatever I don't recommend making the theoretical play but with nothing else to go on I think it's fine to do so. People are very often surprised this is not actually a 50/50 guess on the second round though so I thought I'd mention it.

If what I said did not make sense, another way to look at it is that if they try to balance their Ax(x) play with AJ, ducking a small percentage (equivalent to the amount of time they are dealt AJ doubleton) making your decision on whether they have Ax(x) or AJ tight completely neutral after they win the ace, that means they are winning with Ax(x) a small amount of the time which means it is slightly more likely that the ace is onside than offside after they don't win the ace.

This reasoning even applies with KQT opp xx where obviously AJ doubleton offside is very unlikely, it's still your best strategy in theory. I think this is only practical when you have KQT9xx opp xx and need 2 tricks, in that case when they win the ace on your right there are many examples of good players playing low to the queen on the next round vs other good players. With less cards it becomes more rare to see in real life since AJ doubleton offside becomes more unlikely.

Also, I failed to mention stiff ace, they could have that of course so my explanation is incomplete but basically AJ doubleton is more likely than stiff A.
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#13 User is offline   WellSpyder 

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Posted 2014-March-12, 10:47

Thanks, Justin. I see what you were getting at now (and I found the final paragraph [EDIT: the one about "another way to look at it] a useful additional way of thinking about it, too.)

I must admit I tend not to concentrate too hard most of the time when people get into these sort of game-theoretic discussions since it doesn't seem to have too many implications for how to play the game in practice, but there is no harm in knowing the theory, and maybe I'll take it into account next time I am playing another reader of these forums...
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#14 User is offline   gnasher 

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Posted 2014-March-12, 12:11

View PostJLOGIC, on 2014-March-12, 10:23, said:

Also, I failed to mention stiff ace, they could have that of course so my explanation is incomplete but basically AJ doubleton is more likely than stiff A.

The difference is very small, though: 1.6% against 1.2%, so even a tiny inference is more important.

RHO will be dealt Ax(x) 17% of the time. If he omits to duck as often as one time in 40, it's better to play to the 10 on the second round. (This assumes that LHO will always play low on the second round from Axx or Axxx.)
... 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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#15 User is offline   johnu 

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Posted 2014-March-12, 14:35

An excellent problem in the heart suit illustrating the practical versus the theoretical chances of success.

Against the pure number crunching odds, you need to guess whether LHO is capable of ducking twice (MP or IMPs could be a big factor), or RHO ducking once.

Ducking gives you the best chance of beating the contract, but may give away a hopeless one, or just give up an overtrick.

e.g. If declarer has something like:

Axx
x
Kx
AKQJ10xx

if a high heart is ducked, declarer can ruff the third round of spades. Otherwise, declarer needs a 2nd heart trick.

Assume the first round of hearts is ducked, declarer crosses with a high club to play a 2nd heart.

If you go up on the 2nd round of hearts and it wins, you are cold for 7 by setting up the 5th heart if necessary. If you finesse and drive out the ace, they can play a diamond. Then you need trumps 2-2, hearts 3-3, or the opponent with short hearts not having 3 or 4 trumps. If you guessed wrong, you can make with 3-3 hearts and 2-2 trumps.
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#16 User is offline   HighLow21 

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Posted 2014-March-16, 19:46

If RHO wins A and a diamond comes back, I'm ruffing a diamond high, drawing trumps, and running all trumps but one. I will have to make some guesses, but I figure my odds are better after some detailed distributional information than trying to guess the J (am I finessing it or dropping it at the end?)

To me this beats the pants off of trying to guess the J early. (note: if you do guess the hearts early, I'm almost positive the finesse is the better play, because trying to drop it doubleton or tripleton also requires clubs 2-2.)

By the way, when I'm down to Q, QT, 7 in dummy and Ax, 6, and 8 in hand, then and only then am I cashing the spade Ace. There's just too good of a chance that playing the cards in this order will result in one of the opponents having to blank their last spade prior to the Ace, and the card they follow with may well tell me everything I need to know.

Final point: if the heart ace is ducked, I'd draw trumps and play lefty for the heart ace (or a show-up of the J). To me it's far more likely that the Ace was ducked than that righty made a great hold-up play, his good-player status notwithstanding. Odds-wise, he only needs to grab the ace a very small fraction of the time, I believe, for this to be the percentage play as declarer.

I also don't like the Vienna Coup line--this only improves the odds if they misdefend or if either player has a singleton spade. This is virtually impossible.

Feel free to correct me if I'm wrong--I very well could be.
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