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Can you maximise overtricks risk-free? 3NT MP Pairs

#1 User is offline   jallerton 

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Posted 2015-February-10, 16:48



MP Pairs.

Playing 4-card majors, South opens 1 and gets to 3NT on an uncontested auction. West leads 10.

What's the best line of play?
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#2 User is online   helene_t 

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Posted 2015-February-10, 17:06

Am I allowed to play one or two rounds of spades and watch their count signals? If the spades appear to split I am just taking my ten tricks.

Otherwise I play a club to the nine. If a heart honour comes back I play low but cover the next heart as cheaply as possible. That way they can take no more than three heart tricks I think.
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#3 User is offline   PhilKing 

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Posted 2015-February-10, 17:08

I can only count 8 tricks. :(
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#4 User is offline   jallerton 

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Posted 2015-February-10, 17:41

Sorry, assume the opening lead was 10 (this was the card actually led at the table when declarer had managed to imply diamond shortage in the auction).
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#5 User is offline   mikeh 

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Posted 2015-February-10, 17:56

I will assume few in the field play 5 card majors...if many do, then there is a strong likelihood that those pairs played the same contract from South with a heart lead. If so, then we need to assume the heart A is onside and that we can pick up at least one more trick in clubs.

I think the key here is to not give LHO too much information. Cash the second diamond and lead a club.

From West's perspective, this may look like the hand to play the K or Q from K10x, Q10x. It won't be, since I intend to duck and later play to the Ace.

If he plays, instead, low, then what I play depends on what I think of my opps' skill level. There has been a lot written about how both LHO and declarer should play this layout, and too much for me to try to describe here, not to mention that doing so would likely constitute thread-jacking.
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#6 User is offline   nige1 

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Posted 2015-February-10, 18:44

View Postjallerton, on 2015-February-10, 16:48, said:


MP Pairs.
Playing 4-card majors, South opens 1 and gets to 3NT on an uncontested auction. West leads 10.
What's the best line of play?
Papa Mama: Win A. Cash Q, A, KJ9, chucking 2s and a . AKQ. 2 if it is good. Exit .
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#7 User is offline   jallerton 

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Posted 2015-February-11, 17:31

View Posthelene_t, on 2015-February-10, 17:06, said:

Am I allowed to play one or two rounds of spades and watch their count signals? If the spades appear to split I am just taking my ten tricks.

Otherwise I play a club to the nine. If a heart honour comes back I play low but cover the next heart as cheaply as possible. That way they can take no more than three heart tricks I think.


If you cash two rounds of spades, both defenders follow upwards. They play standard signals, but should they signal honest count in this situation?


View Postmikeh, on 2015-February-10, 17:56, said:

I will assume few in the field play 5 card majors...if many do, then there is a strong likelihood that those pairs played the same contract from South with a heart lead. If so, then we need to assume the heart A is onside and that we can pick up at least one more trick in clubs.


A significant minority plays 5-card majors. Even without that knowledge, I think you are right to consider that other declarers may be favoured by a heart lead - some opening leaders may choose a heart lead (if holding heart length) even when the opening bid was 1.

View Postmikeh, on 2015-February-10, 17:56, said:

I think the key here is to not give LHO too much information. Cash the second diamond and lead a club.

From West's perspective, this may look like the hand to play the K or Q from K10x, Q10x. It won't be, since I intend to duck and later play to the Ace.

If he plays, instead, low, then what I play depends on what I think of my opps' skill level. There has been a lot written about how both LHO and declarer should play this layout, and too much for me to try to describe here, not to mention that doing so would likely constitute thread-jacking.


It's not thread-jacking if you are explaining how you'll play the hand given in the opening post! If West plays the Q from Q10x and you duck, a really alert East might guess what you are up to and overtake.
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#8 User is offline   mikeh 

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Posted 2015-February-11, 18:31

View Postjallerton, on 2015-February-11, 17:31, said:

If you cash two rounds of spades, both defenders follow upwards. They play standard signals, but should they signal honest count in this situation?




A significant minority plays 5-card majors. Even without that knowledge, I think you are right to consider that other declarers may be favoured by a heart lead - some opening leaders may choose a heart lead (if holding heart length) even when the opening bid was 1.



It's not thread-jacking if you are explaining how you'll play the hand given in the opening post! If West plays the Q from Q10x and you duck, a really alert East might guess what you are up to and overtake.


I thought and still think that this is a fascinating hand. I have, however, reconsidered my line of play...I had been writing my first post before you posted that the lead was the diamond 10, even tho I posted some time after you wrote that.

I think it important, once we know at trick one that the diamonds run, to win the A and play a club immediately...not at the speed of light, because we want LHO to have time to think, but just in normal tempo.

He cannot know how many clubs we hold, tho he can infer that we hold the diamond Q he may not be able to infer it is doubleton if we don't allow East to play a second one. On rethinking, it is possible that the auction may have allowed him to infer this, but I won't change what follows, written before I came back to write this sentence.

So West may have to consider xx or xxx in our hand in clubs, and he'll know that we still have a diamond entry, as will east.

what follows may be hazardous to one's mental health

Consider AJ9xx in dummy and declarer with, for simplicity, xx.

We learn early on to play low to the 9, catering to H10x onside, which is twice as likely as KQx.

Then as defender we look at H10x, especially if dummy has no easily used entry, and realize that if we put up the H, declarer has an issue when he has only xx. No matter what he does, he cannot pick up the suit for only one loser if dummy lacks a side entry...we have killed the suit. Even if dummy has an entry, declarer has to win the Ace and then use another entry to cross to his hand to lead low to the J9xx, intending to insert the 9. Compared to ducking, inserting the H from H10x at worst causes declarer to use entries in a different sequence than he was intending, and sometimes he can't afford to use them at all.

Ok, so as a defender we always pop with H from H10x?

Well, if we do that, and on a given hand we play low.....declarer, if alert to our habits, 'knows' we don't have H10x, so since the only other relevant holdings include KQx, he puts in the Jack.

That means that we shouldn't always play the H from H10x...we should mix up our strategy.

What about KQx? Normally we'd play low, since declarer will insert the 9...but will he? H10x is twice as likely as KQx, so whether he should play the 9 or the J depends on how we mix our plays with H10x. If we usually play low from that, then he puts in the Jack. If we usually play H from H10x, he puts in the 9....but what if once in a while we play the K or the Q from KQx? A play that usually means H10x?

Now, he plays us for H10x, wins the Ace, crosses to his hand and leads towards the J9xx, intending to insert the 10....except that partner had 10xx to start with, and we split from KQx, not H10x.

Of course, when we hold KQx, our choice of H to play generates a restricted choice analysis :D

I am not going to take us further down the rabbit hole by discussing AJ9xxx opposite xx or AJ9xx opposite xxx.

As for your last point, yes, an alert East may overtake his partner's Q. That is relatively unlikely, since for that to arise, LHO had to hold Q10x and play the H (many players aren't capable of that, but if this one was, then the chances are that his or her partner is also able to recognize the need for the K), but RHO has to be not only capable of the play but att able to do it....and have a heart suit that makes a shift effective.

As for what I'd do then...hmmmm....given what you wrote about 5 card major prevalence, I think that playing safe here (duck the first heart if an honour, cover the second) is trying to preserve about a 30% - 40% board. If I pop the K and it is wrong, it is costing me about 30-40% of a board, while if I pop and it is right, I am getting a 100% top.

So I'd need to think about whether a zero is going to hurt, compared to a 35% board, more than a top would improve a 35% board, and then think about the opps and how likely is it that rho, in this situation, would shift to a heart honour when holding the A.

IOW, I'd need to be at the table, and even then it would likely depend on my mood.

This is why I play a 5 card major system, of course....I never get to this situation :P I already got my 60% board on the heart lead.
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#9 User is offline   jallerton 

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Posted 2015-February-13, 11:31

If trying to bring the club suit in for one loser, there's a case for playing West for KQx(x) rather than K10x/Q10x(x). Although half as likely, at least when your ideal club layout exists, you are spared the problem of what to do when East switches to a heart. Of course, estimating what will happen at other tables is not an exact science (particularly when you know little about the opponents' hand) and you don't know quite what proportion of the field is being treated to a heart lead.

Anyway, the winning line is neither of these. Let me turn this into a double dummy problem by telling you that:

Spades break 3-3.
East holds K10x and A; West holds Qx.

Two questions:

1. What is the winning line to make 11 tricks?
2. What do you call the end position?
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#10 User is online   helene_t 

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Posted 2015-February-13, 12:01

1. I cash ten winners ending in the hand. If East keeps two clubs I exit a heart and vice versa.
2. A squeeze without the count?
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#11 User is offline   nige1 

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Posted 2015-February-13, 14:33


Thank you JAllerton for the pretty problem.
On the left is the ending suggested by Helene_t.
Declarer (South) cashes 2 to squeeze RHO.
Declarer exits in whichever suit RHO abandons.
Terence Reese might call it a Winkle.

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