Mind Games

[Finch]

BAM (point-a-board in English) against a very strong pair

 

p.s. this hand is made-up, of course, but it's based on an IMPs hand from last night

 

[hv=pc=n&s=s83hakt4daj853ca6&n=skj9h73dkt92ck842&d=s&v=e&b=3&a=1dp2d(inverted)p2h(natural%20unbalanced%20%5B5+%20diamonds%5D)p2s(stop)p3n(%20extra%20values)ppp]266|200[/hv]

 

South has shown strong NT values with 4 hearts and 5 diamonds.

5 of spades lead, 9, queen, 3

6 of spades, 8, Ace, Jack

4 of spades, King, 2, heart discard

 

They play standard leads & signals, so in theory West has shown up with A10752 of spades and East Q64.

How do you play the diamond suit?

[mfa1010]

The bidding is revealing enough so that west should not have been worried that his partner only had 2 spades.

 

I don't see west winning the second spade with ♦x. He can't see through the cards and there would be a good chance that east could have a diamond stop with ♦A or ♦QJx.

 

I don't see him win the second spade with ♦Qxx either since in practice it clearly increases his risk of being finessed in diamonds.

 

Ergo I don't know who to finesse, so I'll play for the drop. I think it is most likely that west has ♦Qx. He might have given up or tried to a avoid a spade endplay.

[phil_20686]

Shouldn't i hook into rho always? If lho led from Axx its percentage (Axx is not a pretty lead, so much more likely to have a hand with no long suit so needs three diamonds), if lho led from ATxxx then its an avoidance play, and you have extra chances after you have four diamonds in the bag. Not great extra chances, but ATxxx xxxx xx xx for example.

[Cyberyeti]

Why hasn't W ducked the second spade ? Does he think you might have 11 other tricks ?

 

I think for him to think this, he has 2 diamonds (or 3 small) so I'm probably playing for the drop.

 

If he's failed to duck with Qxx good luck to him, he's gained nothing, I was getting it wrong anyway.

 

So is he really likely to fail to duck with a small singleton ? Very risky, it's conceivable the contract is ZP on this layout and partner will be getting in anyway (xx, AKxx, Axxxx, AQ), and he's just found the way of letting it through.

[mfa1010]

Well done east if he was able to win the queen trick 1 from QTxxx. How should he work that out when p leads a middle-ish spot card.

[Fluffy]

I like this hand, against people I know that are poker pros I'd go random or pehaps just safety (6♦ -1 is not unthinkable at the other table). But I am inclined to think a good player is blocking on purpose and that I should finese East.

 

 

This situation is very similar IMO to dummy having a winner but no entry except for the KJx opposite our doubleton. In practice all players I meet hop the ace in from of KJ, and every player hooks the jack because of that.

[dboxley]

I think that any time W has the DQ he would automatically duck the second spade to give declarer a guess so it should be automatic to play E for the DQ. I dont think this is a double think situation. He just might take to second spade at BAM to avoid the overtrick. Who knows? It doesn't seem right not to duck in any case, are you sure this is a very good pair?

[nige1]

A clever theme! A games-theorist could work out the optimum mixed-strategy in ♦

 

In practice, I think Frances should take the money rather than try to out-think fiendishly cunning opponents. Assuming it is unlikely that RHO has brilliantly won trick one with ♠Q insead of ♠T, you can (almost) guarantee the contract by playing LHO for ♦Q. If you mastermind the play to go down in 3N, you will not impress your other pair who defend 5♦ or defeat 3N or 6♦.

[phil_20686]

Perhaps west has xxx clubs and was concerned about conceding 12 tricks when opener has 2353 with 9 minor sout tricks.

[mike777]

A clever theme! A games-theorist could work out the optimum mixed-strategy in ♦

 

In practice, I think Frances should take the money rather than try to out-think fiendishly cunning opponents. Assuming it is unlikely that RHO has brilliantly won trick one with ♠Q insead of ♠T, you can (almost) guarantee the contract by playing LHO for ♦Q. If you mastermind the play to go down in 3N, you will not impress your other pair who defend 5♦ or defeat 3N or 6♦.

 

 

 

geez I have no idea what you talk about

 

"games theorist work out mixed strategy"

 

 

fwiw if you are going to talk about fiendisly difficult hands prefer you spell it out in very simple terms thanks

 

 

yes I know this is expert forum but.....

[gnasher]

This is a bit pathetic, but against a *very* strong West, I'm not going to try to out-think him. I'll just do what I would have done if he'd ducked the second spade. I think that means I finesse against East, partly because of vacant spaces and partly because of the failure to overcall - ♦Q might have been enough to swing him from not overcalling to overcalling.

 

Against a normally strong West, a likely reason for his play is an expectation that the diamonds will come in, combined with a fear of being endplayed to lead from Qxx in another suit. Any holding such as xxx, xx, x or Qx might lead him to think that the diamonds are coming in, so we can't glean much from that. The one thing we can be sure of is that he doesn't have ♦Qxx, where he would have ducked, expecting us to go wrong in the suit. If, however, he is worried about being endplayed to lead from a round-suit holding, that reduces the space for ♦Q in his hand. Hence I still finesse against East, but for different reasons.

[gnasher]

♦Q might have been enough to swing him from not overcalling to overcalling.

 

On reflection, a singleton diamond might also have been enough to induce him to overcall. Which is the better overcall, A10xxx Qxx x Jxxx or A10xxx Qxx Qx Jxx?

[Fluffy]

nice self-debate :). I think singleton is better than Qx, and that's what a good LHO would think. There are point counters who would think Qx is better, but they are unrelated to the OP

[dave_w]

I'll just do what I would have done if he'd ducked the second spade.

 

I think this is right. Though I disagree with the finesse - it's got to do with information that opponent's give you versus information you gather yourself. We shouldn't be surprised that West chose to lead from a 5 card Spade suit. If East had of been on lead and had led their (possible?) 5 card club suit then would we claim vacant spaces and finesse West for the Diamond Queen. Playing like this means you'll mostly finesse opening leader's partner due to vacant spaces. Even when both hands have 5 card suits. I don't like it. I'll play for the drop because that's what I was doing anyway.

[gnasher]

I think this is right. Though I disagree with the finesse - it's got to do with information that opponent's give you versus information you gather yourself. We shouldn't be surprised that West chose to lead from a 5 card Spade suit. If East had of been on lead and had led their (possible?) 5 card club suit then would we claim vacant spaces and finesse West for the Diamond Queen. Playing like this means you'll mostly finesse opening leader's partner due to vacant spaces. Even when both hands have 5 card suits. I don't like it. I'll play for the drop because that's what I was doing anyway.

I think the vacant spaces argument does apply. This isn't like the standard example where it goes 1NT-3NT and they lead a five-card suit. Given the bidding, LHO would probably not lead from a five-card red suit, so the lead tells us that West's longest black suit is five cards long.

 

Using Pavlicek's calculator, I make it that the chance that his longest black suit is:

6 or more: 11%

Exactly 5: 30%

4 or fewer: 59%

so the lead tells us to expect a larger than average number of black cards in his hand.

Edited May 31, 2012 by gnasher

[wanoff]

We know diamonds are not 3-1 so cash AD and play for 2-2 or West having all 4.

[dave_w]

I think the vacant spaces argument does apply. This isn't like the standard example where it goes 1NT-3NT and they lead a five-card suit. Given the bidding, LHO would probably not lead from a five-card red suit, so the lead tells us that West's longest black suit is five cards long.

 

Using Pavlicek's calculator, I make it that the chance that his longest black suit is:

6 or more: 11%

Exactly 5: 30%

4 or fewer: 59%

so the lead tells us to expect a larger than average number of black cards in his hand.

 

I disagree that LHO wouldn't lead a 5 card Heart suit. Also I think vacant spaces tells us that he doesn't have a 5 card Diamond suit to lead from.

Either way it shouldn't surprise us that he chose to lead a Spade when he has 5 of them (ie his odds of having another 5 card suit are now remote anyway).

I think your argument is backwards - looking at the odds of different length spade suits - because that tells us his a priori odds of different length Spade suits. What I want to know is what is LHO's expected Spade length WHEN he leads a Spade. I suspect the answer to that is over 4. Thus this isn't enough evidence to sway my play in Diamonds.

 

I just realised something weird about the hand: If I knew West had led from 3 Spades then at BAM I would finesse him for the ♦Q and at IMPs I'd finesse his partner. Nice hand Frances!

[twoshy]

Even if our very strong LHO was worried about 12 tricks being taken after a second round duck, why wasn't the ♠T returned? We then wouldn't be able to rule out ATx opp Qxxxx. Of course, it is quite tough to lead from ATx.

 

Depending on how LHO perceives us, the defender could be angling for us to...

- Take a safe finesse into RHO

- Take a vacant spaces finesse into LHO (though I have no idea if this applies, re: dave_w's argument)

- Play for the drop in diamonds

- Finesse (or not) in clubs, our jack being located elsewhere

- Finesse (or not) in hearts

- presumably some others, too!

 

This is way too much for me, so I'll just play for the drop, as I would have done after seeing the ♠T on either the second round (Txx/AQxxx potentially) or the third round (ATx/Qxxxx potentially). Enjoying the discussion, cool hand.

[Finch]

No-one has yet objected to the play at trick one, which a friend has convinced me is wrong. Or at least definitely wrong at imps, and more interesting at BAM.

[dave_w]

No-one has yet objected to the play at trick one, which a friend has convinced me is wrong. Or at least definitely wrong at imps, and more interesting at BAM.

We can take two spade tricks with either QT onside or AQ onside. Opponents don't lead from AQxx but do lead from QTxx. So for 2 tricks we should play the 9.

 

For one trick things are different. If the opponents win the ♠Ten and return another suit and subsequently get in and lead another Spade then we are at a guess for our trick. We can pay out to a lead from Qxxx/Axxx/Txxx (or longer) If LHO has 5 Spades then he'd always lead a Spade. If LHO has 4 Spades then he'd always lead from the Queen, only sometimes from the Ace, and from the Ten it depends on the rest of his hand but I'd think it's more likely than from the Ace. All this leaves me mostly confused .... I definitely want to play the Jack at some point - but I don't see that it has to be at trick one.

 

From a whole hand perspective the danger is the ♠9 loses to the Ten and a Heart comes back. We have to win that (explaining to team mates how we went down in this contract with Diamonds 2-2 by losing the first 5 tricks will be hard). And then we play three rounds of Diamonds losing to the Queen and they play another Heart and we haven't established our ninth trick (indeed there might not be any winning line from here).

 

(sorry about the spot cards - but I didn't look at the full hand)

 

So at BAM I play the ♠9 (best chance for two tricks IMHO). At IMPs I play the ♠J to establish a fast trick (hopefully).

 

Someone is going to complain that it's a guess at IMPs but the point is that we want to win quickly - the opponents might always be able to beat us with the AQ offside but why give them the chance to beat us with AT offside also!

 

eg this is the danger layout for E-W

[hv=pc=n&w=st832hq932d4cj932&e=saq54hj84dq32cq64]266|100[/hv]

 

There's no way home now (except guessing Diamonds .... but the Diamond Queen can be moved and you'll pay off to a different layout).