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How to avoid the 7H trap

#1 User is offline   inquiry 

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Posted 2008-August-13, 22:52

This hand is from the English open trials. Both teams reached 7H, doomed by the 4-1 trump split, when 13 tricks are there for the taking in NT (and spades for that matter).

Scoring: IMP

Both tables started the same....
1 - 2
2 - 3

At one table, north rebid 4, at the other bid 4. In both auctions, south took control with blackwood.


--Ben--

#2 User is offline   P_Marlowe 

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Posted 2008-August-14, 02:16

Hi,

The question is, can you detect that the spade suit is solid,
more precise can you detect the jack of spades ?

Both South believed that to the added chance, that one can make
7H even with spades breaking 4-2 is worth risking the 4-1 trump
break, the 4th jack being with West, i.e. this risks occurring with
approx. 10%?
4-1 with 25%, Jack not singleton and 4 card with West, ... hopefully
I got the calculation right.

I agree.

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Marlowe
With kind regards
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#3 User is offline   gnasher 

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Posted 2008-August-14, 02:23

If South bids 7 opposite two aces and K, I think that North should convert the final contract to 7NT. He knows that South has A, AKQ, and either KQ or both minor kings.

If South has KQ, 7NT makes whenever 7 does, and will usually make even if there is a heart loser.

If South has A AKQx Kxx Kxxxx, 7 gains over 7NT when both black suits are bad but hearts break. 7NT gains when there's a trump loser but you can make enough tricks from the club finesse plus a long black card (or a squeeze). The latter is more likely.

The only South hand I can think of where 7 is clearly best is something like A AKQJ Kxx Kxxxx.
... 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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Posted 2008-August-14, 02:46

I agree with Andy. If anyone can find it, it's North, not South.
I must admit I would have bid the same as at the table at least until 7.
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#5 User is offline   gnasher 

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Posted 2008-August-14, 03:43

gnasher, on Aug 14 2008, 09:23 AM, said:

The only South hand I can think of where 7 is clearly best is something like A AKQJ Kxx Kxxxx.

I've thought of another. Maybe North was worried about A AKQx KQx xxxxx or Ax AKQx KQxx xxxx. On these hands 7 is better, because you don't need the long spade.
... 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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#6 User is offline   mike777 

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Posted 2008-August-14, 06:56

Assuming South asks for Aces...North shows two.



Now when South asks for specific Kings North knows we have all the Keycards and should risk jumping to 6s to show a running suit. 6s when hearts are trumps does not just show the K. South can always sign off in 6nt or NOrth can respect South's decision to reject 7nt and play in 7H.

Otherwise if North does not bid 6s as others have said then convert 7H to 7nt.
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Posted 2008-August-14, 07:45

After blackwood, both souths made a grand slam try, and both north's jump to 7. Once South shows all keycards (and heart queen) with a grand slam try, it is true that north knows spades are solid (after all, he can see the J), but north also can think a diamond ruff might be the 13th trick....

How to solve the problem that a diamond ruff is not necessary?
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#8 User is offline   mike777 

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Posted 2008-August-14, 07:48

inquiry, on Aug 14 2008, 08:45 AM, said:

After blackwood, both souths made a grand slam try, and both north's jump to 7. Once South shows all keycards (and heart queen) with a grand slam try, it is true that north knows spades are solid (after all, he can see the J), but north also can think a diamond ruff might be the 13th trick....

How to solve the problem that a diamond ruff is not necessary?

?

Just bid 6s and let south decide. 6 spades over specific King ask should let South know spades are running.
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#9 User is offline   jdonn 

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Posted 2008-August-14, 10:18

I think north can always convert at the end, there seem to me clearly more hands with AKQx of hearts in south's hand that have 13 top tricks than there are hands where the long spade is needed as a 13th trick.
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#10 User is offline   jmc 

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Posted 2008-August-14, 12:41

I thought it was standard for North to bid 7c accepting the grand try and indicating a choice of slams. Here I would assume that choice would show good spades. South can then choose 7H or 7NT. Maybe I am wrong about this treatment.

jmc
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#11 User is offline   benlessard 

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Posted 2008-August-14, 13:19

I think north was lazy to pass 7H.

5C+4S+1D+4H= 14

You simply dont need a D ruff.

If the clubs dont run its because partner has KQ of D anyway.
2C+3D+4H+4S=13
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#12 User is offline   ASkolnick 

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Posted 2008-August-14, 14:03

1S-2C
2H-3H
4C-4D (We cue bid kings)
4H-4N
5H-5N
6C-6D (K of clubs), I have stuff in diamonds
7N

North knows of
5S-3H-2C-3D (Has to be at least KQ now).
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#13 User is offline   dburn 

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Posted 2008-August-14, 14:56

gnasher, on Aug 14 2008, 04:43 AM, said:

gnasher, on Aug 14 2008, 09:23 AM, said:

The only South hand I can think of where 7 is clearly best is something like A AKQJ Kxx Kxxxx.

I've thought of another. Maybe North was worried about A AKQx KQx xxxxx or Ax AKQx KQxx xxxx. On these hands 7 is better, because you don't need the long spade.

South might have explored for an eight-level contract with the second hand, of course.

But might not South have held A10x AKQ8 xxx Kxx? 7NT requires both the club finesse and four heart tricks opposite that, while 7 needs only 3-2 hearts, or 4-1 with the length in East. If South's clubs happen to be Qxx 7NT is very poor, 7 still good (though a spade lead may complicate matters when it comes to taking two diamond ruffs).

You would not respond 2 with those South hands? Well, what would you respond? For myself, I think it highly dangerous for North to go around overruling South after the latter has used Blackwood and placed the contract. Maybe he knew what he was doing.
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#14 User is offline   mike777 

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Posted 2008-August-14, 14:59

dburn, on Aug 14 2008, 03:56 PM, said:

gnasher, on Aug 14 2008, 04:43 AM, said:

gnasher, on Aug 14 2008, 09:23 AM, said:

The only South hand I can think of where 7 is clearly best is something like A AKQJ Kxx Kxxxx.

I've thought of another. Maybe North was worried about A AKQx KQx xxxxx or Ax AKQx KQxx xxxx. On these hands 7 is better, because you don't need the long spade.

South might have explored for an eight-level contract with the second hand, of course.

But might not South have held A10x AKQ8 xxx Kxx? 7NT requires both the club finesse and four heart tricks opposite that, while 7 needs only 3-2 hearts, or 4-1 with the length in East. If South's clubs happen to be Qxx 7NT is very poor, 7 still good (though a spade lead may complicate matters when it comes to taking two diamond ruffs).

You would not respond 2 with those South hands? Well, what would you respond? For myself, I think it highly dangerous for North to go around overruling South after the latter has used Blackwood and placed the contract. Maybe he knew what he was doing.

That is why I think bidding 6s over specific K ask is best and letting South place the contract. I agree. We may end up playing this hand in 6nt or 7H. Granted this hand is pretty minimum across from some lite opening bids and this hand may not be so fast to start rkc.
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#15 User is offline   jdonn 

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Posted 2008-August-14, 15:21

dburn, on Aug 14 2008, 03:56 PM, said:

You would not respond 2 with those South hands?

I would. But you would bid blackwood after one cuebid from partner with that hand, rather than cuebidding 4 so partner can use blackwood and you can show your whole hand? If that's true then I think 'figurative' you should sign up for bidding lessons with 'actual' you.
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#16 User is offline   dburn 

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Posted 2008-August-14, 15:46

jdonn, on Aug 14 2008, 04:21 PM, said:

dburn, on Aug 14 2008, 03:56 PM, said:

You would not respond 2 with those South hands?

I would. But you would bid blackwood after one cuebid from partner with that hand, rather than cuebidding 4 so partner can use blackwood and you can show your whole hand? If that's true then I think 'figurative' you should sign up for bidding lessons with 'actual' you.

One of the bidding lessons I would give myself is "when you have the ace-king-queen of trumps, don't expect partner to take control of the auction". Certainly on this occasion, with partner having solid spades and both minor-suit aces, he would be well placed to do so once I went beyond game - but that is not something I could have predicted in advance.
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#17 User is offline   gnasher 

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Posted 2008-August-14, 16:30

dburn, on Aug 14 2008, 09:56 PM, said:

But might not South have held A10x AKQ8 xxx Kxx?

I don't know what the full auction was at either table, but if South had enough information about North's hand to be able to bid 7 with A10x AKQ8 xxx Kxx, why didn't he bid 7NT with A3 AKQ8 KQ9 KT65 ?
... 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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#18 User is offline   jdonn 

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Posted 2008-August-14, 16:34

gnasher, on Aug 14 2008, 05:30 PM, said:

dburn, on Aug 14 2008, 09:56 PM, said:

But might not South have held A10x  AKQ8  xxx  Kxx?

I don't know what the full auction was at either table, but if South had enough information about North's hand to be able to bid 7 with A10x AKQ8 xxx Kxx, why didn't he bid 7NT with A3 AKQ8 KQ9 KT65 ?

Because the south who held the made up hand didn't fully satisfy his zest for life with the blackwood overbid :)
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#19 User is offline   dburn 

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Posted 2008-August-14, 18:15

gnasher, on Aug 14 2008, 05:30 PM, said:

I don't know what the full auction was at either table, but if South had enough information about North's hand to be able to bid 7 with A10x AKQ8 xxx Kxx, why didn't he bid 7NT with A3 AKQ8 KQ9 KT65 ?

Scoring: IMP

The full auction at one table (Hallberg North, McIntosh South) was 1-2-2-3-4-4-4-4NT-5-5NT-7. The full auction at the other table (Justin North, Jason South) was 1-2-2-3-4-4NT-5-5NT-6-7.


This is not quite what the original post suggested, since both Norths bid 4 and neither 4, and at the first table North appeared to make the final decision for his side. I don't know why North bid 7 rather than 7NT at the first table, nor what 6 meant at the second table, but perhaps following 6 South imagined North with the queen of clubs in a hand such as Kxxxx Jxxx Ax AQ (when 7NT would not be a very good contract at all, while 7 would not be a bad one).
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Posted 2008-August-14, 21:23

My auction (incredibly easy hand):

OPENER: 1
RESPONDER: 2
OPENER: 2
RESPONDER: 3
OPENER: 3 (two of the top three honors in spades)
RESPONDER: 3NT (Serious 3NT)
OPENER: 4 (Ace or Queen of clubs)
RESPONDER: 4NT (RKCB)
OPENER: 5 (I have two without the Queen)

At this point, Responder knows that Opener has the two minor Aces, with KQ-fifth in spades. When Responder makes a grand try, the prior 3 cuebid comes in handy, as this allows Opener to know that Responder has the spade Ace and is looking for the spade Jack. So...

RESPONDER: 5 (do you have the spade Jack?)
OPENER: 5NT (yes)

At this point, the entire hand is known. Opener is known to have nine cards in the majors (at least), and hence four cards in the minors. The A-K-Q of diamonds and A-K of clubs are overkill. This guarantees a major card pitch. We are now known to have the Ax in spades opposite KQJxx (at least) and AKQx opposite xxxx in hearts (at least), needing only eight tricks from these suits.

We could have the spade 10, spade 9 establuishing, heart J, heart 10 establishing, heart hook marked, etc. If spades split 5-0, the hearts may come in. If hearts split poorly, the spades may come in. If nothing works in the majors, a squeeze may be on. Easy 7NT call now. 7 would be wildly inferior.

Interesting that Responder still has room to make a lot of other inquiries if he is not satisfied bidding a 98% grand.
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