BBO Discussion Forums: Matchpoints is hard - BBO Discussion Forums

Jump to content

Page 1 of 1
  • You cannot start a new topic
  • You cannot reply to this topic

Matchpoints is hard

#1 User is offline   smerriman 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 3,720
  • Joined: 2014-March-15
  • Gender:Male

Posted 2021-September-26, 14:25


After a somewhat dubious robot auction, you arrive in 3NT, and West leads the club 6 to East's king.

I like playing game after an opponent has opened the bidding, since you can guess where most honors are (though West may still have something).

But with entries to dummy limited, what's the best plan at matchpoints?
0

#2 User is offline   mikeh 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 12,835
  • Joined: 2005-June-15
  • Gender:Male
  • Location:Canada
  • Interests:Bridge, golf, wine (red), cooking, reading eclectically but insatiably, travelling, making bad posts.

Posted 2021-September-26, 16:29

I’m primarily an imp player, and never go swinging for the fences in what seems like a reasonable contract, especially when I’ve got a favourable lead. LHO is marked with 4+ hearts and a heart lead would have created some issues.

I also don’t play robot tournaments so I can’t judge how often other declarers will be faced with the club lead…I think robots are so appalling that I don’t consider it to be an enjoyable pastime….in fact, having played too much solitaire, I’m pretty sure that robot bridge is bad for one’s game


With those caveats, I think it pretty clear to lead a diamond to the Jack. This pretty well guarantees an overtrick, losing 2 diamonds and a club.

Obviously if opener has AQ tight in diamonds, I’d do better by crossing in spades and leading a low diamond, but that’s so low percentage (as LHO has room for the diamond Queen, and RHO has room for 3 diamonds) that I’m not risking my decent score for 3N on a favourable lead.
'one of the great markers of the advance of human kindness is the howls you will hear from the Men of God' Johann Hari
0

#3 User is offline   Winstonm 

  • PipPipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 17,190
  • Joined: 2005-January-08
  • Gender:Male
  • Location:Tulsa, Oklahoma
  • Interests:Art, music

Posted 2021-September-27, 12:15

I think the key issue here is as Mikeh pointed out - you have avoided a heart lead and surely that by itself puts you well ahead of at least part of the field. I think the goal now should be 10 tricks by keeping opener on lead so I duck the opening lead. The best return for them is a spade. I win the king and bang down the K of diamonds. The idea is that by the time west can get in with his possible diamond queen my 10 tricks are established.
"Injustice anywhere is a threat to justice everywhere." Black Lives Matter. / "I need ammunition, not a ride." Zelensky
0

#4 User is online   pescetom 

  • PipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 7,203
  • Joined: 2014-February-18
  • Gender:Male
  • Location:Italy

Posted 2021-September-27, 12:50

View PostWinstonm, on 2021-September-27, 12:15, said:

I think the key issue here is as Mikeh pointed out - you have avoided a heart lead and surely that by itself puts you well ahead of at least part of the field. I think the goal now should be 10 tricks by keeping opener on lead so I duck the opening lead. The best return for them is a spade.

I too would duck, figuring it is unlikely to cost and they might solve me a problem.
But then my opponents are not in the same league as those of mikeh.
0

#5 User is offline   smerriman 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 3,720
  • Joined: 2014-March-15
  • Gender:Male

Posted 2021-September-27, 13:08

My first thought:

a) It's possible that East may hold a 3 card club suit (indeed, in the actual hand, they did). What happens if you duck the first trick?

If East switches to a heart or diamond, obviously, you're delighted. If they continue clubs, you will immediately know the club break from West following with something higher than the 3. You can now afford to overtake the spade king with the ace, and finesse diamonds twice - getting +2 if the queen is onside, and still +1 if not.

Perhaps it's obvious to a good defender that the only continuation is a spade into dummy (overtaking still works, but declarer no longer knows that), but if you were planning to play to the diamond jack next time, as far as I can see it looks worth putting them to the test first.

My second thought:

b) What happens if you win the first club, then overtake the king of spades anyway before running the jack of diamonds?

If the queen is offside, you've lost the overtrick (though are still making game).

If the queen is onside, once the ace is knocked out you can cash your spades, diamonds, and club queen, ending in hand with Ax hearts and x clubs. Now if East started with more than 3 clubs (which you'll know when West plays to the queen), he must hold onto Kx of hearts, so you can exit with your last club for +2. If East had 3 clubs, you cash out for +1.

(It's possible I've made a mistake in my calculations somewhere but I think that's all right.)

As mentioned by others, the expectation that others would be in 3NT on a different lead is a huge factor - though here (and this is the only part where the robot factor comes in) identical auctions lead to identical leads, and I'd expect several of those - and it's difficult to calculate the odds that the queen is onside, though it seems to me likely as placing it with West requires placing both jacks with East for the opening bid. But it seems worth considering.
0

#6 User is offline   mikeh 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 12,835
  • Joined: 2005-June-15
  • Gender:Male
  • Location:Canada
  • Interests:Bridge, golf, wine (red), cooking, reading eclectically but insatiably, travelling, making bad posts.

Posted 2021-September-27, 14:11

I think it dangerous to assume that this was the only route to 3N or, indeed, the most common route.

As an example, I would have overcalled 1N and would expect that to be ‘a’ popular choice if not ‘the’ popular choice

Now many north’s would use stayman….at mps I prefer 3N. After any 1N overcall,I’d think that even robot defence might get a heart lead.

As for ducking the club, if they switch to a heart, I win in dummy and advance the diamond Jack. Now, if Dealer opened on, say, xx KJxx Ax KJ107, I’m going down in a cold contract.

Is this likely? No…but even at mps one rarely risks a cold contract.

One might/should if, as an example, one is in 3N and can see that 4M has 11 tricks while we only have 10 in 3N….and can play for 11 only by risking going down in 3N (or, less dramatically, being held to 9 tricks). If one thinks that most of the field will be in the major, then at mps one risks the disaster, while at imps you take the 1 imp loss.
'one of the great markers of the advance of human kindness is the howls you will hear from the Men of God' Johann Hari
0

#7 User is offline   AL78 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,962
  • Joined: 2019-October-13
  • Gender:Male
  • Location:SE England
  • Interests:Bridge, hiking, cycling, gardening, weight training

Posted 2021-September-27, 15:41

View Postmikeh, on 2021-September-27, 14:11, said:

Is this likely? No…but even at mps one rarely risks a cold contract.


There is one MP situation where I am never sure whether it is worth taking a risk with the cost being going down if it fails. Say you are in 3NT that it looks like everyone will be in (e.g. a 1NT - 3NT auction), the defence attack your weakest suit and knock out your only stop (and you can't hold up enough to exhaust one of them of that suit). You have an easy nine tricks and a finesse which will give you a tenth trick if it works, or the defence will cash their suit and get you down if it fails. Assuming you have nothing in the play to hint where the honor card is, do you take the finesse?
0

#8 User is offline   smerriman 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 3,720
  • Joined: 2014-March-15
  • Gender:Male

Posted 2021-September-27, 15:53

View Postmikeh, on 2021-September-27, 14:11, said:

As for ducking the club, if they switch to a heart, I win in dummy and advance the diamond Jack. Now, if Dealer opened on, say, xx KJxx Ax KJ107, I’m going down in a cold contract.

Ah, yes, that's a good point.

While this will probably put you off this thread entirely, the robots lead a spade with the 1NT auction. +2 was 98%, +1 66%, = 24%. I'm not sure how to calculate whether the second line is worth the risk, but I think given those odds, it might well have been.

View PostAL78, on 2021-September-27, 15:41, said:

There is one MP situation where I am never sure whether it is worth taking a risk with the cost being going down if it fails. Say you are in 3NT that it looks like everyone will be in (e.g. a 1NT - 3NT auction), the defence attack your weakest suit and knock out your only stop (and you can't hold up enough to exhaust one of them of that suit). You have an easy nine tricks and a finesse which will give you a tenth trick if it works, or the defence will cash their suit and get you down if it fails. Assuming you have nothing in the play to hint where the honor card is, do you take the finesse?

Often I find that if you cash all of your other tricks first, the defenders end up having to discard in a such a way that you can afford to gamble the finesse at the very end, as they'll then give you your last trick back if it loses.
0

#9 User is online   Cyberyeti 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 13,897
  • Joined: 2009-July-13
  • Location:England

Posted 2021-September-27, 16:43

View Postmikeh, on 2021-September-26, 16:29, said:

I’m primarily an imp player, and never go swinging for the fences in what seems like a reasonable contract, especially when I’ve got a favourable lead. LHO is marked with 4+ hearts and a heart lead would have created some issues.

I also don’t play robot tournaments so I can’t judge how often other declarers will be faced with the club lead…I think robots are so appalling that I don’t consider it to be an enjoyable pastime….in fact, having played too much solitaire, I’m pretty sure that robot bridge is bad for one’s game


With those caveats, I think it pretty clear to lead a diamond to the Jack. This pretty well guarantees an overtrick, losing 2 diamonds and a club.

Obviously if opener has AQ tight in diamonds, I’d do better by crossing in spades and leading a low diamond, but that’s so low percentage (as LHO has room for the diamond Queen, and RHO has room for 3 diamonds) that I’m not risking my decent score for 3N on a favourable lead.


Are you really guaranteed an overtrick ?

What are you going to do if E wins Q and returns 6 or 7 ? if you play low, W wins and switches to a heart and your overtrick vanishes, if you rise, W shows out and you're off. Your suggestion of KJ107 as E's club holding would mean W led small from 63 which I'd guess we'd be told if that was systemic, so 3-3 or 5-1 are more likely.
0

#10 User is offline   smerriman 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 3,720
  • Joined: 2014-March-15
  • Gender:Male

Posted 2021-September-27, 16:49

View PostCyberyeti, on 2021-September-27, 16:43, said:

Your suggestion of KJ107 as E's club holding would mean W led small from 63 which I'd guess we'd be told if that was systemic, so 3-3 or 5-1 are more likely.

West led the 6 - 63 is perfectly viable.
0

#11 User is offline   pilowsky 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 3,620
  • Joined: 2019-October-04
  • Gender:Male
  • Location:Israel

Posted 2021-September-27, 17:01

What were the GIB alerts?
Did the 2 bid mean "good support in diamonds"?
And what did the 3 bid mean?
0

#12 User is offline   mikeh 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 12,835
  • Joined: 2005-June-15
  • Gender:Male
  • Location:Canada
  • Interests:Bridge, golf, wine (red), cooking, reading eclectically but insatiably, travelling, making bad posts.

Posted 2021-September-27, 17:56

View PostCyberyeti, on 2021-September-27, 16:43, said:

Are you really guaranteed an overtrick ?

What are you going to do if E wins Q and returns 6 or 7 ? if you play low, W wins and switches to a heart and your overtrick vanishes, if you rise, W shows out and you're off. Your suggestion of KJ107 as E's club holding would mean W led small from 63 which I'd guess we'd be told if that was systemic, so 3-3 or 5-1 are more likely.

If east returns the club 6 I call for the director, since west originally led that card.

If he returns the 7, someone is doing or has done something strange.

The 7 makes no sense from any combination other than an eccentric J107 or K73, but with the latter, west would lead the Jack from J106.

It would be brilliant for east to led the 7 from J107, since if I popped the (edit…I wrote the ace but that was played at trick one, so I should have written the Queen), he holds me to 9 tricks. But it would be just as idiotic as it is brilliant…if I floated it to the 9, I take 11 tricks.

Since very few defenders lead the 6 from J106, if east does return the 7, I’m ducking it.
'one of the great markers of the advance of human kindness is the howls you will hear from the Men of God' Johann Hari
0

#13 User is online   Cyberyeti 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 13,897
  • Joined: 2009-July-13
  • Location:England

Posted 2021-September-28, 03:37

View Postmikeh, on 2021-September-27, 17:56, said:

If east returns the club 6 I call for the director, since west originally led that card.

If he returns the 7, someone is doing or has done something strange.

The 7 makes no sense from any combination other than an eccentric J107 or K73, but with the latter, west would lead the Jack from J106.

It would be brilliant for east to led the 7 from J107, since if I popped the (edit…I wrote the ace but that was played at trick one, so I should have written the Queen), he holds me to 9 tricks. But it would be just as idiotic as it is brilliant…if I floated it to the 9, I take 11 tricks.

Since very few defenders lead the 6 from J106, if east does return the 7, I’m ducking it.


Sorry I read it as the original lead was the 3, he will return the 3 in that case, partner had 1076 or stiff 6.

It's not completely idiotic to return the 3 if he has all of them, he may decide he's rouletting a 30% score into a zero with a chance of getting a top if you misguess, if he's looking at all the points, he will realise partner has found a dud lead.
0

#14 User is offline   mikeh 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 12,835
  • Joined: 2005-June-15
  • Gender:Male
  • Location:Canada
  • Interests:Bridge, golf, wine (red), cooking, reading eclectically but insatiably, travelling, making bad posts.

Posted 2021-September-28, 08:38

View PostCyberyeti, on 2021-September-28, 03:37, said:

Sorry I read it as the original lead was the 3, he will return the 3 in that case, partner had 1076 or stiff 6.

It's not completely idiotic to return the 3 if he has all of them, he may decide he's rouletting a 30% score into a zero with a chance of getting a top if you misguess, if he's looking at all the points, he will realise partner has found a dud lead.

No way west led a stiff club….well maybe a robot might, but that would make them evening worse than I think they are. If east returns the 3, clubs are 3-3, so I win the Queen to prevent a heart switch and to cement my overtrick
'one of the great markers of the advance of human kindness is the howls you will hear from the Men of God' Johann Hari
0

Page 1 of 1
  • You cannot start a new topic
  • You cannot reply to this topic

1 User(s) are reading this topic
0 members, 1 guests, 0 anonymous users