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How do you defend here?

#1 User is offline   AL78 

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Posted 2020-May-19, 15:28

This deal came up last week with a friend of mine (our club is now a virtual one on BBO) who is an aspiring novice.



North dealer. I don't know the auction, other than North played in 3NT which made for a near bottom EW, because only one other NS pair bid it. Deep Finesse says it should be held to eight tricks, but I am looking at this trying to see where my friend and her partner could have done better, and it does not look easy at all to get 3NT down.

As a wild guess, NS were playing Acol, weak NT:



This is the only way I can think how they got there.

East leads the spade six, which gives declarer a tempo to set up a second spade winner. Declarer can also lead toward the club king for another trick. Added to the five diamond tricks and two major aces brings the total to nine tricks, so EW have to move quick and be very precise how they establish their five tricks. It looks like the spade lead was fatal, but who wouldn't lead a spade if this was the auction? Anyway, looking at all four hands and rewinding back to before the opening lead, I can't see an obvious way to stop 3NT, the defence can establish a couple of heart tricks with the club ace, but beyond that it looks as though whatever black suit they try to attack helps declarer as much as them. What am I missing here? What I am trying to do is go through my friend's bad scores and advise where she could have done better, and there is theoretically a way to do better here, but how, and how would even a decent intermediate find it at the table? If the killing defence at the table could only be found by a pair of internationals then fair enough, I'll put it down to random crappy nonsense.
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#2 User is offline   hrothgar 

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Posted 2020-May-19, 15:44

The fact that a double dummy defense to 3NT exists doesn't mean that it can / should be found at the table.

I suspect that DF's defense is based on leading the Queen of Clubs followed by a heart shift if this holds
Alderaan delenda est
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#3 User is online   smerriman 

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Posted 2020-May-19, 16:14

Add a contract to the handviewer, then use the GIB and Play buttons:



East has to lead a heart honor; if North ducks then continue with a low heart. Then they sit back and wait for enough tricks.

But this is obviously just a double dummy solution; they got a bad score because their opponents bid to a terrible game and got lucky. Conversely you can get a good score by playing badly; analysing mistakes independently of scores and double dummy is a fine art.
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#4 User is offline   nudnikbp 

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Posted 2020-May-20, 05:26

When posting, it is critical to provide the exact auction.
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#5 User is offline   AL78 

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Posted 2020-May-20, 08:08

View Postnudnikbp, on 2020-May-20, 05:26, said:

When posting, it is critical to provide the exact auction.


Unfortunately I don't know the exact auction.

As it happens, someone has pointed out the killing defence is a heart honor which is never going to be found at the table in reality, so I can put it down to a NS fluke.
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#6 User is offline   Cyberyeti 

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Posted 2020-May-20, 09:28

In practice J probably beats it, big call to fly the K at trick 1
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#7 User is offline   armantt2k 

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Posted 2020-May-20, 10:30

(BTW, HOW DO YOU PUT THIS HAND INTO BBO TO PLAY/PRACTICE AND SEE WHAT GIB DOUBLE DUMMY SAYS?)

With a Club J lead, obviously ducked, W cannot return Clubs.

A Diamond return doesn't hurt N, and it looks like EW can setup at least 2, or 2-3 along with 3 (not 4) tricks.
But on either a Spade or Heart return by W, N can set up a second winner/stopper in that suit.

Assuming E wins the 2nd trick and leads another Club, N can even hold up the Club K one more time to confirm W is out ("So that's why W didn't he return Clubs!")

Now N can win the next E lead on the 4th trick (having taken her losers early!), and can get back to his hand to lead thru the marked Club Ace to take the K (if that wasn't the 4th trick).
After that, simply run the long Diamonds before taking the 3 tricks she carefully built in the Majors, making 9 tricks.

I don't see how EW can set up and take their 5 tricks before N accomplishes this.

Perhaps EW can set up 2S+2H+1C before N can get the job done?
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#8 User is offline   TomSawyer4 

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Posted 2020-May-20, 12:22

I remember this hand, although its inverted NS. The auction was:
!NT-P- 2C - X -
2S -P- 2NT - P -3NT - All Pass.
As I recall, GIB, in its usual wisdom, lead a diamond.
Since the Ace of clubs is marked by the bidding, making nine tricks was/is easy from there.

Before you ask, no, it was not a weak no-trump. It was, and is, a standard 15-17 NT, combined with a lot of experimenting with exactly how GIB responds to 1NT bids. I won't explain further on this issue.
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#9 User is offline   Cyberyeti 

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Posted 2020-May-20, 13:36

View Postarmantt2k, on 2020-May-20, 10:30, said:

(BTW, HOW DO YOU PUT THIS HAND INTO BBO TO PLAY/PRACTICE AND SEE WHAT GIB DOUBLE DUMMY SAYS?)

With a Club J lead, obviously ducked, W cannot return Clubs.

A Diamond return doesn't hurt N, and it looks like EW can setup at least 2, or 2-3 along with 3 (not 4) tricks.
But on either a Spade or Heart return by W, N can set up a second winner/stopper in that suit.

Assuming E wins the 2nd trick and leads another Club, N can even hold up the Club K one more time to confirm W is out ("So that's why W didn't he return Clubs!")

Now N can win the next E lead on the 4th trick (having taken her losers early!), and can get back to his hand to lead thru the marked Club Ace to take the K (if that wasn't the 4th trick).
After that, simply run the long Diamonds before taking the 3 tricks she carefully built in the Majors, making 9 tricks.

I don't see how EW can set up and take their 5 tricks before N accomplishes this.

Perhaps EW can set up 2S+2H+1C before N can get the job done?


Incorrect, if Q wins, W returns a heart, if N ducks , E wins and returns a small heart ducked to the A, now dummy is an entry short, to establish the spade you have to lead from dummy, the K is no longer an entry, and if you cash it having entered dummy with A before playing the spade, W has clubs to cash when in with K, if you don't you never get it.
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#10 User is offline   dsLawsd 

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Posted 2020-May-20, 14:13

Touch and go contract, but do not lead a spade. I guess depending on the auction to lead J at matchpoints but as always declarer may work out a winning line.

passive leads sound good and may often work, but when holding a fair hand speed may be important and partner could likely not have a good spade hand but might have hearts...

Excellent question.
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#11 User is offline   xHx 

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Posted 2020-May-21, 06:46

It's easy! :)
When solving double dummy problems you cannot consider mistakes, as other answers to this post suggest.
N cannot take 9 tricks on accurate defense. And that would be, taking in consideration all possible ways that this board could unfold, the following:
First of all the lead has to be K or J

1) If N takes the first round and:
a) play clubs right away he will make 1 + 5 + 1 = 7 tricks and when he will try to establish his 2nd spade trick E would have an entry with his other heart honor to cash the good clubs;
b) crosses with A to dummy to play the Q in order to establish the spade trick first, W will cover, N wins with A and plays 10(else is similar to 1.a)); now, W takes his J and continues spade, setting up the suit with Q as an entry when E wins the first round of clubs with the A;

2) If N ducks first trick, E continues with 7, now:
a) N tries to first establish the club trick, E takes the first round of clubs and unblocks K in order to set up his partner Q to be cashed when getting in with the J. In this case the declarer is hold to 1 + 1 + 5 + 1 = 8 tricks.
b) N crosses to dummy with A in order to set up a 2nd spade trick, W covers the Q and ducks! the 10 in order to preserve the defense communication...now declarer can make 2 + 1 + 5 = 8 tricks and when tries the finesse in clubs, E takes his A and cashes his K and exits his well preserved spade in order to cross to W fot him to cash his Q as well, for the defense to take 1 + 3 + 1 = -1

3) Declarer tries to break the defense communication by taking the first trick and continues with a heart, now E has to play small in order to let his partner in with the Q, now W will have to play his stiff Q, E overtakes with the A and continues with a high club in order to set 2 more club triks, having his other heart honor serving as entry to the clubs. Defense takes 3 + 2 (+1 if declarer tries to set up a spade trick instead of cashing his 8 tricks)

This lead could be made on proper information from the bidding(I cannot comment on that since there is no bidding attached) and very good understanding of the game. After the mandatory lead, the defense could prevail with good logic, precise counting and figuring out how they can take 5 before declarer takes 9(a bit more complex than intermediare bridge skills, but not that out of reach). I would say that the play on trick 2 would be crucial(considering the optimal lead and the duck from declarer), if first 2 tricks go well for the defense the contract will probably go down.
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#12 User is offline   nordicone 

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Posted 2020-May-21, 08:10

I think if E leads the J of C instead of a S, and continues this allows EW to get 4 clubs and a S
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#13 User is offline   AL78 

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Posted 2020-May-29, 12:43

View Postnordicone, on 2020-May-21, 08:10, said:

I think if E leads the J of C instead of a S, and continues this allows EW to get 4 clubs and a S


That doesn't work. Declarer wins and leads the Q through West (covered else it is over for the defence), then knocks out the J. West can lead a heart but declarer wins and now has nine tricks (5 diamonds, 2 spades, K and A).

The killing lead is the K, which immediately sets up communication between the defending hands, and after knocking out the A, the defence can establish the required tricks in whatever suit declarer attacks and have the heart communication to cash them. It has to be the K so East can play a small heart to knock out the ace if declarer ducks, and have the flexibility in the heart suit for either defender to put the other on lead, depending on who has established black suit tricks.

I'd challenge any expert, or even world class player to find that defence at the table.
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