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Make the slam You got there, now make it...

#1 User is offline   Hanoi5 

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Posted 2011-September-08, 09:01



Q is led.

View Postwyman, on 2012-May-04, 09:48, said:

Also, he rates to not have a heart void when he leads the 3.


View Postrbforster, on 2012-May-20, 21:04, said:

Besides playing for fun, most people also like to play bridge to win


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#2 User is offline   inquiry 

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Posted 2011-September-08, 13:27

Unless I am missing something terrific clever, there isn't much information to consider here, so it reverts almost to a straight forward math problem (something I am not wonderful at).

First, you can not afford to lose two hearts. There are some heart holdings where you can avoid losing two hearts. A 5=0 split, either way, East or West with KT9x of hearts. You will lose two hearts if West has a singleton King (double dummy you wouldn't but this isn't double dummy).

How you play the rest of the hand depends on what happens in hearts. If East has Kx of hearts, you would be playing for an overtrick.

It is obvious that with a spade ruff in dummy, you will have 12 tricks if you avoid losing two hearts (4, 2. 1 ruff, 3, 2). So the first (and probably only problem on this hand) is of West drops the nine or ten of hearts when you play a heart to the Jack. You have to decide if you want to give up on the straight-forward line of ruffing a spade in dummy to protect against the 1=4 split. To protect against East having KTxx or K9xx when West drops the NINE or TEN on first round of hearts, you would lead a low heart towards the queen. Now you will not get your spade ruff (not, with T9x or Tx or 9x west should drop a high heart to cause you to consider this play). If you give up on the straight forward line (one spade ruff) after the middle high heart from West, you will need to either play to drop the Jack or for a minor suit squeeze, or hook one of the two opponents. To squeeze East in the minors, the club threat might have to be the third small club in your hand. Double dummy, you can always guess the Jack right, and single dummy you can perhaps find enough clues to either play for the squeeze or have good insight in who to finesse for the jack later in the hand (you need to keep entries flexible to be considering a discovery play-based finesse).

All in all, I guess we would all win the ACE and play a heart to the JACK (if east plays low). If West wins the heart king, we play for a spade ruff in dummy, if West plays a small heart, we cash the heart Ace and play for a spade ruff in dummy, if West plays the 9 or T, I will play low to the queen. Did West show out? I assume East returns a heart to stop the pending spade ruff. If he had only Kx of hearts, then he can not return a spade. If I can't ruff a spade, I will have to consider the distributional clues before deciding how to handle diamonds. Chance of dropping jack in the short hand is not great (around 36%), chance of diamond finesse is better (50%). If I can get a vacant space clue to figure out who might be the favorite to hold the diamond jack, I might go with the straight forward finesse. With no vacant space clues, the combined chances of dropping the diamond jack or squeezing an opponent with 4 to the JAck and any four plus clubs is extremely close to the 50% of playing for the diamond finesse. At the moment, not taking any vacant space into account, the finesse is 50%, the squeezes calculates out to be more than 49.5%. However, if east had four heart to West 1, that will reduce the chances of the squeeze, and increase the chances of the finesse through West, so I will go with that (picking up singleton jack with East along the way). This is about 53%.

I am considering moving this thread to interesting hand or general bridge forum, as not sure a math problem is suitable for advanced play forum. It would have been a nice defensive hand with West holding Tx of hearts, however, and to have west drop the ten on the first round.

--Ben--

#3 User is offline   gnasher 

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Posted 2011-September-08, 14:23

View Postinquiry, on 2011-September-08, 13:27, said:

I am considering moving this thread to interesting hand or general bridge forum, as not sure a math problem is suitable for advanced play forum.

I don't think it's just a maths problem. Apart from anything else, there might be a compound squeeze. It's certainly difficult enough to remain in the A/E forum.

I'm probably in a minority, but I think you should be cautious about moving threads around. Unless it's obviously misplaced I think it's better to leave it where you found it.
... 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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#4 User is offline   ArtK78 

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Posted 2011-September-08, 14:38

Why not win the spade in hand and play a heart towards the Q in dummy? I then will cash the other spade, cross to my hand and ruff the spade loser.

This wins whenever trump are 3-2 and when trump are 4-1 with a singleton K in LHO's hand as long as I can ruff the spade successfully and not suffer a ruff in getting back and forth between the hands. And there are some other chances if it turns out that LHO has the K and a spade doubleton.
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#5 User is offline   gnasher 

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Posted 2011-September-08, 15:40

View PostArtK78, on 2011-September-08, 14:38, said:

Why not win the spade in hand and play a heart towards the Q in dummy? I then will cash the other spade, cross to my hand and ruff the spade loser.

This wins whenever trump are 3-2 and when trump are 4-1 with a singleton K in LHO's hand as long as I can ruff the spade successfully and not suffer a ruff in getting back and forth between the hands. And there are some other chances if it turns out that LHO has the K and a spade doubleton.

It may also let you cope with singleton 9 or 10 in West, though you have fewer squeeze options than in Ben's line.
... 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   johnu 

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Posted 2011-September-09, 01:28

I would win the A and lead the Q from dummy. If it loses to LHO, win the return, draw another round of trump, and try to ruff a spade. If it is covered, win the ace and try to ruff a spade. If the spade ruff is successful, lead the 7 from dummy cover anything from RHO. This line can't handle singleton K offside, but you can pick up king fourth onside by force for 1 loser except for K1096.

If RHO has K1096 and is 3-4-3-3, 3-4-4-2, you can play 3 rounds of diamonds pitching a club, ruff a diamond, play 2 clubs ending in dummy and lead a club from dummy for a trump coup.


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#7 User is offline   rhm 

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Posted 2011-September-09, 02:20

View PostHanoi5, on 2011-September-08, 09:01, said:



Q is led.

You obviously need 4 tricks and giving up on the ruff to cater for some 4-1 breaks is not a sensible single dummy proposition.
So the issue is how many 4-1 trump breaks can you cater for while still ruffing your loser?
Playing low to the trump queen caters for the singleton trump king on your left but little else. LHO can and should false-card with 109x.
So finessing the 8 on the next round of trumps is not sensible.
This is particularly true if you start by playing low to J, where a false card is mandatory to give declarer a losing option when RHO has Kx.
Playing the ace of trumps is better, since it caters for the singleton king on either side, but again not much else.
Since you want to ruff your spade loser in dummy, give up on 4 trumps to your left and concentrate making the slam when 4s are on your right.

The best I can come up with is to win the A and run the Q. If this looses to the king you need trumps to be breaking.
But if it gets covered, you are in good shape if LHO drops the ten or 9, and with some chances even if LHO follows with a low .
Next ruff your spade loser with the 7. If this gets over-ruffed you will have to decide whom to play for the other intermediate, should it not pop up on the next round.
Given that s are 6-2, this is a difficult decision. On a restricted choice basis it is probably best to play for the drop.
If you did not get over-ruffed, play a trump for a finesse of the 8. If RHO follows low, you are home. So let's assume RHO splits from an original K109x.
You now need a trump coup to score your 8 en passant. For this to work RHO needs 3 and 2 plus one further card in the minors.
Play 4 rounds of and ruff the last in hand to shorten your trumps. Next play AK ending in dummy.
At trick 12 you are sitting with 8x over RHO Tx. So the only trick opponents get is the T

T1: A
T2: Q. RHO covers.
T3: K
T4: ruff with 7. If this works
T5: 5 for a finesse of the 8. Assume RHO splits the T,9 and you win with the J, LHO showing out.
T6-8: AKQ discarding loser
T9: ruff
T10-11: AK ending in dummy
T12: from dummy to score your 8 en passant for your 12th trick.

The chances for the slam to make this way is hard to calculate, but when neither opponent has bid , should be better than 70%.

Rainer Herrmann
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#8 User is offline   gnasher 

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Posted 2011-September-10, 02:28

View Postrhm, on 2011-September-09, 02:20, said:

Playing low to the trump queen caters for the singleton trump king on your left but little else. LHO can and should false-card with 109x.
So finessing the 8 on the next round of trumps is not sensible.

After a heart to the 10, queen and king, you win the return and cash A. If everyone follows, you ruff a spade in dummy; if LHO shows out on the second trump you cross to dummy, take a heart finesse, and later make another trick somehow.

Quote

The best I can come up with is to win the A and run the Q.

What will you do if Q holds?

(Another reason for keeping the thread in the Advanced/Expert forum is that it means we can assume advanced/expert defence.)
... 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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#9 User is offline   rhm 

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Posted 2011-September-10, 16:20

View Postgnasher, on 2011-September-10, 02:28, said:

After a heart to the 10, queen and king, you win the return and cash A. If everyone follows, you ruff a spade in dummy; if LHO shows out on the second trump you cross to dummy, take a heart finesse, and later make another trick somehow.

As I said in my first sentence I do not deem it sensible to give up on the spade ruff in preference to cater for a 4-1 break. Admittedly you give up on the spade only after you found out about the 4-1 break.
Nevertheless "Make another trick somehow" means your chances making the slam almost drop by 50%. Note that on Johnu and my line we cater for LHO having a singleton ten or 9 without having to look for another trick somehow.
Making the 8 en passant via a trump coup is only necessary if LHO has the singleton 6 or 2

Quote

What will you do if Q holds?

That is a rather favorable development for our line, because RHO will not have KT9x. Of course the second finesse gets delayed. Come to the K and ruff first the loser with the 7 in case LHO has ducked from Kxx.
If both opponents follow to the third round of , we are home, unless RHO shows out on the second , in which case our line never stood a chance from the start and I said I would give up trying to make when LHO has 4s.
Since I am going to try to ruff a spade always (even if LHO would show out on the first , which is not hopeless on our line), the duck can only gain in a very unlikely scenario: If RHO has 10x or 9x and less than 3 cards in s.
Would West have kept quiet at favorable vulnerability over 1 with QJxxxx and Kxx ? In my experience the answer is No.

Rainer Herrmann
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#10 User is offline   gszes 

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Posted 2011-September-10, 21:02

dont want to go down if trumps are 32
so we try to cater to 32 splits and
SAFE 41 splits while keeping a spade
ruff in mind. I would win trick one
in hand and lead low toward the Q.
This is actually better than playing
to the A to pick up stiff K in W hand.

If heart holds come back to ace and
go for spade ruff. If heart loses win
pull one trump and go for spade ruff
(unless lho shows out)

this line loses to stiff K in rho hand
(and some bad spade splits)
but keeps options alive for all other
situations. There is no real problem if
LHO play 10/9 trick 1 and rho wins the K
we cash 1 top trump and know right away
if ruffing a spade is safe or not.

That means rho with K (t or 9) xx has to
duck the first round of spades and risk
completely losing any trump trick to a
safety play VERY hard to do(especially at
MP)
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#11 User is offline   rhm 

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Posted 2011-September-11, 02:12

View Postgszes, on 2011-September-10, 21:02, said:

dont want to go down if trumps are 32

Sorry, but this is nonsense.
You can always go down on 3-2 trump breaks if LHO ruffs in or RHO over ruffs the , since you will always ruff the before drawing the third round of trump, because otherwise there will be no trump left in dummy.
Ruffing a is obviously not safe, but is far more likely to succeed than all the alternative options looking for a 12th trick somewhere.
It is even much less likely that RHO has a doubleton trump with the 9 or ten and less than 3 cards in and to boot LHO having passed over 1 will duck the Q.

Quote

so we try to cater to 32 splits and
SAFE 41 splits while keeping a spade
ruff in mind. I would win trick one
in hand and lead low toward the Q.
This is actually better than playing
to the A to pick up stiff K in W hand.

Not true since A also picks up the stiff K in the East hand.

Quote

If heart holds come back to ace and
go for spade ruff.

Loses also to all 4-1 splits, where LHO holds 4 s

Quote

If heart loses win
pull one trump and go for spade ruff
(unless lho shows out)
this line loses to stiff K in rho hand
(and some bad spade splits)
but keeps options alive for all other
situations. There is no real problem if
LHO play 10/9 trick 1 and rho wins the K
we cash 1 top trump and know right away
if ruffing a spade is safe or not.

If LHO has the stiff 6 or stiff 2, you are down on this line.
If LHO has a stiff 9 or T and you do not ruff a you have to look for a 12th trick somewhere else. Your chances for that are not much better than 50% now.
My educated guess is that on your line it would probably still be a better proposition trying to ruff the loser and play for a trump coup against RHO instead of looking for another trick somewhere. However, that is close.

Quote

That means rho with K (t or 9) xx has to
duck the first round of spades and risk
completely losing any trump trick to a
safety play VERY hard to do(especially at
MP)

This is nonsense. I guess you meant s not in your statement, since RHO can only duck the K . But even then it does not make sense.
Why should RHO duck at all? You pretend all the time as if you have - single dummy - a sure line finding another trick if you do not ruff the .
Well if this would be the case, nobody would try to ruff the loser in the first place.

Rainer Herrmann
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#12 User is offline   gszes 

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Posted 2011-September-11, 21:51

sigh I reread my post and saw the language problems

If lho plays (t or 9) to the first trump (not spade sigh) trick (not trick 1
but trick 2 when leading low toward the trump Q)

aside from that my proposed line gives us a non guess LOP that allows us to
pull two rounds of trumps and cut the danger of an opps spade ruff almost in
half by making sure the only way we get beat trying for a spade ruff is if
one opp has a doubleton spade and 3 trumps (with at least T or 9).
If trumps break 4/1 we can pick up most RHO 4/1 holdings at the expense
of ruffing a spade and then we have to hope we guess dia since squeeze
probabilites look excceedingly thin. If LHO has stiff heart K we can still
go for our spade ruff as the best shot of scoring an extra trick.


The downside of banging down the heart A first is that if the K
(only 2 cases and leading low toward the trump Q caters to singleton K
with LHO) does not fall you then have to guess how to proceed
and not trying to pull 1 trump leaves both defenders in position
to possibly ruff the 3rd round of spades and if you try to pull
another trump you lose your spade ruff when Kxx exists (in either hand)
<12 cases> and they return 3rd trump.

A heart to the J followed by a heart to the Q has the same problem
when Rho has Kxx (6 cases) and if lho ducks heart to the J with Kxx
(12 cases)

Successfully running the heart Q leaves you in a guessing state and
once again leaves you in a no win scenario (6 cases) if lho started
with kxx and you repeat the finesse.

This is not meant to be a 100% LOP but one that gives us the best
shot at managing the normal 32 trump split and still allowing us
a chance to guess diamonds with many 41 trump splits when rho has
the trumps.
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#13 User is offline   rhm 

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Posted 2011-September-12, 06:28

Let's face it

That s break 6-2 or worse is a priory less than 20%.
With the opponents passing throughout at favorable vulnerability (East passed originally, West over 1) does not make a 5-3 or 4-4 break a certainty, but much better than 80%. My estimates is chances are way above 90%. The Q opening lead does not change these facts substantially.

If you lead the Q at trick 2, there is no guess how to continue if it holds. You ruff your loser first before continuing with another finesse.

Leading the Q looses outright, whenever LHO has 4 cards in s or the singleton K.
It wins when LHO has the singleton T or 9 without having to search for another 12th trick.

If LHO shows out on the first , leading the Q is the only play which gives you a chance.
You then have to play RHO for 3=5=3=2, which is his most likely distribution now. It does not matter whether RHO covers.
Ruff your with the 5, cash your minor suit winners ending in dummy.
In the 4 card ending, when you play a minor card from dummy, declarer and RHO is down to only s. Cover RHO cheaply and play a to the 7.
RHO gets only one trick.

The remaining 4-1 cases are that LHO has the singleton 2 or 6. Again leading the Q is the only play, which still leaves you with a chance of making.
You will now make if RHO has 3=4=3=3 or 3=4=4=2 or 2=4=4=3. If RHO makes the mistake of over-ruffing the when he holds 2 cards in you will always make.
I have described the play for this case before.

If we compare this to leading low to the Q at trick 2.

If trumps break 3-2, the outcome is almost identical. We both try to ruff a .
A very slight difference is that on leading the Q, we will ruff a after drawing only one round of trumps instead of two, if the Q holds.
The chances that this matters is negligible.

Leading low to the Q gains only if LHO has a singleton king --> one case where leading the queen looses
You have clearly worse chances making if LHO has singleton 9 or ten --> 2 cases where leading the queen wins
You have no chance if LHO has no or the singleton 2 or 3 --> 3 cases where leading the queen wins

Rainer Herrmann
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