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Would like to learn more about Endplays

#1 User is offline   spotz 

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Posted 2013-August-19, 10:00

I've read a few Endplay examples which explain how to execute but none of the examples explain how to identify the opponent to be "thrown in". Is it just a guess that's only expected to work 50% of the time like a finesse? If you have a link to a resource on the topic, I'd be very interested in looking it up.

Thanks
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#2 User is offline   barmar 

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Posted 2013-August-19, 10:18

Sometimes you know, for instance if the other defender has already shown out of the suit, their earlier play has marked them for the card, they bid the suit.

Other times, it's a matter of hoping that the cards lie the way you need, because it's the only way to make the contract.

#3 User is offline   Cyberyeti 

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Posted 2013-August-19, 11:40

The endplay can also be a safety play: Spades are trumps, you can afford to lose only one trick



You can guarantee the contract unless west has all 4 trumps, play small to the Ace and if nobody shows out, finesse on the second round, either it wins and you have no trump loser, or it loses and W has to lead a diamond picking up the suit for you or give you a ruff and discard.

It's just a question of visualising whether only one opponent can be thrown in as in my case, or whether just exiting at the right time will do the job (leaving a trump and A10x opposite a trump and KJx in the same side suit).
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#4 User is offline   mikeh 

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Posted 2013-August-19, 15:24

The series is, I suspect, long out of print and I don't know how easy the books are to find on the internet, but in the 1980's (maybe the late 70's) Reese and Trezel co-published a series of small books on various aspects of technique. One dealt largely with elimination plays, which is another way of describing endplays: endplays always require that the player being endplayed has no exit card other than one that hands declarer a trick, and this often requires declarer to cash cards such as to 'eliminate' the defender's safe option.

You can buy it online: I just checked and Amazon has it, tho at an absurd price. Maybe I should think about selling my collection if Amazon's prices are realistic!

The series is actually pretty good, tho had they put all the books into one book it still wouldn't have been a huge book, and the cost would have been a lot lower (which was, I suspect, the point of multiple books).
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#5 User is offline   spotz 

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Posted 2013-August-19, 23:23

My limited understanding is that the suit in question is avoided until the end so how would a defender show out of that suit? I guess I'm looking for an explanation that teaches how to make this kind of determination.


View Postbarmar, on 2013-August-19, 10:18, said:

Sometimes you know, for instance if the other defender has already shown out of the suit, their earlier play has marked them for the card, they bid the suit.

Other times, it's a matter of hoping that the cards lie the way you need, because it's the only way to make the contract.

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#6 User is offline   Mbodell 

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Posted 2013-August-20, 01:42

View Postspotz, on 2013-August-19, 23:23, said:

My limited understanding is that the suit in question is avoided until the end so how would a defender show out of that suit? I guess I'm looking for an explanation that teaches how to make this kind of determination.


You would know because the throw in suit doesn't need to be the endplay suit.

For instance assume that you've already run and (nobody has any left) and while that was happening West pitched a club. And now this is what you have left:



When you cash the first three rounds of clubs, West shows out on the third round. You now know that West started with 3 clubs so East had 4 and East is going to win the 4th round. But once East does he'll have to play a diamond. You now have endplayed East if he held the diamond K.

Also, sometimes the throw in is in the suit in question. Imagine we've cashed all the spades, hearts, and diamonds, so everyone has only 3 clubs left in their hand each and the lead is in the South. The classic endplay position is:



You play up to the N hand and cover cheaply whatever W plays. Now you are guaranteed 2 tricks. If W plays the K, you win A and Q. If W plays one of the J or T you will play the Q, and either: It wins and you get Q and A; or: it loses but now E is on lead and must play a club to your A9 and only one of the J or T is out, the other plus the K was played on the first trick, so you'll get both of these too. If West plays a low card, you play the 9 and now either this wins (and you get the 9 and A) or it loses and East must lead back into the AQ for two tricks.
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#7 User is offline   Free 

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Posted 2013-August-20, 02:41

It depends a lot on the hand. Basically you have to determine how the suit needs to be played to determine which opponent you want to throw in. Sometimes there are several options available for one holding.
- KJ9 (dummy) opposite AT8: it doesn't matter which opponent plays the suit. Throw them in in another suit.
- AQ9 (dummy) opposite 432: you want RHO to play into AQ9. Here you can use the same suit to throw in RHO so you lose only 1 trick in this suit.
- A3 (dummy) opposite Q2: here you have to hope that the player who's thrown in (using another suit) has to underlead his King in this suit. If LHO leads the suit you let it run to your Q, if RHO plays the suit you go up with the Q.
- AJ2 (dummy) opposite T43: in general, it doesn't matter who's endplayed here. You always let it run. When RHO leads, then either LHO plays K or Q and you can develop the J or T. When LHO leads, then you let it run to your T and hope LHO underlead from KQx (small chance) or RHO takes and you finesse later hoping LHO underlead Kxx or Qxx. However, when you're sure that RHO has KQx you have to endplay RHO (for example by playing to the J, after which you have a similar situation like the previous example)

All these examples suppose that opps can't play another suit (for example all other suits have been eliminated and you have a trump left in both hands).
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#8 User is offline   inquiry 

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Posted 2013-August-20, 20:30

View Postspotz, on 2013-August-19, 23:23, said:

My limited understanding is that the suit in question is avoided until the end so how would a defender show out of that suit? I guess I'm looking for an explanation that teaches how to make this kind of determination.


Endplays come in a variety of flavors. Let's look at one suit in isolation.
Dummy Spade = Q32
Declarer Spade = J54

If you have to "open" (lead this suit) you chance of winning one trick is fairly low. If you lead low from one hand, the next hand might have singleton A or K or doubleton AK solving the problem instantly. In addition, when you lead towards the Queen (or the Jack) if the next hand has both the AK and some small cards you will win one trick. What exactly the odds of these are is not important, but it is fairly low.

When you have a suit like this, if you can FORCE the opponent to lead this suit you are 100% certain to win a trick. So for instance if you come down to a five card ending where you have that spade suit, a losing club in each hand, and a trump in each hand with the opponents out to trumps, you can lead the club and let them win it. Your opponent has two choices. Lead a spade, allowing you to win one spade trick (plus a trump) or lead another suit and allow you a ruff and a sluff which is just as good.

Notice it didn't matter which opponent you let win the "endplay" trick. That is, many times the endplay works against either opponent.

At other times there will be a danger opponent. That is one, who if he gets in, can do great damage to your position. Perhaps he has winners he can cash. Perhaps he can lead a suit through your hand to your detriment where his partner has no such exit card. Or perhaps he just has a "safe" exit card when his partner does not. In these cases you aim to throw the non-danger opponent in for the endplay.

There are a lot of free stuff on the internet dealing with endplays. Most of it is very short and perhaps not too useful. There are books, Mikeh suggest one I have, but he is right it is small and expensive. An old one I liked was George Coffin's "Elimination in Bridge". Others exist, like David Bird's "Endplays for everyone" which can be found for around ten dollars used. Perhaps you should try to get a used copy of one of these or similar books. In fact, quite a few bridge clubs I have played at have lending libraries and if you look around, you might find an endplay book at a local club, or find a local bridge player who will loan you a copy.

There are a wide variety of places on the web that discuss endplays (the topic is wide). Perhaps a good way to learn is to google endplays and watch how hands were played to execute them. You will also find various educational content on endplays. These range from simplistic power point presentation (few examples), to a webpage with six examples when you hold certain card combinations like the one I listed above (Discussion of card combinations useful for potential endplays, to things with short essay like classes (one such example, A second example). I have even seen youtube video lesson on endplays (not worth the time involved to watch them). I even have authored a BBO movie available for free online that deals with "vulnerable stopper endplays" link to the bbo movie, You can read reviews and details on this movie here in the forum (BBF forum review). However, understand that the vulnerable stopper endplay lesson deals with only one type of endplay and some of the hands you will be asked to solve in that interactive movie are quite difficult.

I guess the web needs a well written endplay primer. Perhaps some forum member could team up to collaboratively work on one.
--Ben--

#9 User is offline   SteveMoe 

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Posted 2013-August-20, 22:07

Would add a few books you might want to check:
Clyde Love's book Bridge Squeezes Complete has a chapter on end plays.
Eddie Kantar offers several examples in Take all your Chances (and I think there are some in Take all your Tricks too--both of which are very good reads Take your time with each hand).
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#10 User is offline   Siegmund 

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Posted 2013-August-21, 18:58

There is also David Bird's Endplays for Everyone, at a very introductory level, that does quite a good job explaining the why-and-how of the simpler kinds of endplays.
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#11 User is offline   barmar 

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Posted 2013-August-23, 17:01

Here's a hand I just played that shows how you can infer the endplay from the bidding and play.

From the auction, East should have most of the missing high cards -- West can have at most one Queen; this is very useful information.

East correctly played the 8 on the opening lead, hoping West had the 9 and this would force me to win my Ace (I might bid 2NT holding A2, so West was leading from 953), but I won the 9. This didn't seem to cost a trick for the defense, because I was always going to get 2 hearts with this layout (but see later). You can count 8 sure tricks: 2 clubs, 4 diamonds, 1 heart already won and 1 top heart. If West has the Q I can get a 9th trick by finessing the Jack. I can also get a 9th trick if clubs are 3-3 one of the defenders has the doubleton queen, or East has Qxxx. The auction suggests that the Q is more likely to be with East, so looking for a trick in clubs seems to have a better chance. But there's no rush.

I played 4 rounds of diamonds, to start getting a count of the hand. East showed out on the last one, discarding a low spade. So now it looks like East started with either 3=5=3=2 shape or Ax KQxxx xxx Qxx. So I played the AK, and the queen fell doubleton, and I had my 9 tricks.

But this is matchpoints, so overtricks are very important. East pitched a when I led a to the Jack. This strongly suggests that he he started with AQx, but I don't really care where the Queen is. I played A and another , and East was end-played. He could cash his last , but would then have to lead away from his A. He was squeezed on the 3rd -- if he didn't pitch a , he would have to have pitched the Q, setting up a spade trick for me.

It turns out that playing low on the opening lead did cost a trick. If he'd gone up, then instead of me end-playing him, he could have end-played me. Timing is important. :)

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