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Daily Quiz Recap Peek

Posted By: Stick
Date: Sunday, 24 July 2011, at 8:30 p.m.

In Response To: Dorbel v. Stick - Remarkable backgame defense (Taper_Mike)

I chose this problem as one of those to include in my last daily quiz recap. Now that you bring it up I wish I would have included more but the play really was clear to me once I decided I didn't want to play the strictly no hitting 23/16. Pasted below is from the DQR:

Number 1 from 6/27
is Player 2

score: 3
pip: 200
11 point match
pip: 128
score: 9

is Player 1
XGID=aaacBBCBBB----b--aabbAaA--:1:1:1:52:9:3:0:11:10
to play 52
1.XG Roller++6/1* 4/2* eq: +0.501
Player:
Opponent:		76.99% (G:53.00% B:7.10%)
23.01% (G:2.81% B:0.11%)
2.XG Roller++23/21 6/1* eq: +0.491 (-0.011)
Player:
Opponent:		75.85% (G:55.44% B:8.07%)
24.15% (G:1.92% B:0.07%)
3.XG Roller++9/7 6/1* eq: +0.462 (-0.040)
Player:
Opponent:		74.70% (G:56.38% B:9.68%)
25.30% (G:2.36% B:0.09%)
4.XG Roller++23/18* 4/2* eq: +0.461 (-0.040)
Player:
Opponent:		74.52% (G:51.51% B:7.59%)
25.48% (G:2.15% B:0.08%)
5.XG Roller++9/2* eq: +0.456 (-0.046)
Player:
Opponent:		74.14% (G:55.94% B:11.16%)
25.86% (G:1.98% B:0.08%)
6.XG Roller++23/16eq: +0.451 (-0.050)
Player:
Opponent:		73.97% (G:49.75% B:6.08%)
26.03% (G:2.06% B:0.07%)

I've included this position from my match at FIBS. It is an excellent example about how to defend against backgames. I didn't bother with a rollout. I feel very confident that 6/1* 4/2* is the best play at any score. People have a hard time even seeing this type of play. (XG included, it wouldn't analyze this play past 1 ply, you have to push it through the filter for it to realize its worth) Once you've studied backgames seeing and even making this sort of play becomes second nature. What are you afraid of, that you're breaking a 6 prime and leaving 27 shots?! No ... what you're afraid of is that with any other play your opponent is able to make a second anchor and time his backgame. What you're hoping to do in this particular position is get, I don't know, say 8 or 9 of your opponent's men back and then let the front of his position collapse completely. When your opponent has 8 checkers back and the other 7 of his men have all been pushed to the two point and beyond he has no game no matter how many anchors he has. He isn't at the front of your prime and has no real offensive position of his own so recycling your checkers in hopes of cracking his position completely so this type of prime breaking shot leaving play carries very little risk with it. The reward is big when you are able to make him crunch or even stack more of his men on the same inner board point, your 3pt in this position.

The other important aspect of this position that you won't get until you play it out a few times is how often you end up closing your opponent out and him having anywhere from 6-9 checkers that can only enter on your 3 point. At the score the power of this is lessened a bit but it's an important lesson for when gammons and backgammons do matter. Think of all the immediate sequences where you go for and easily achieve the closeout of those men. When your opponent rolls [66 55 65 63 53] this is the variation that is most likely to happen. You then cover two points and pound away easily. That's almost a fourth of all games!

I played this game out many times to see how it unravels. Below are a couple interesting positions I arrived at from playing it out and after that are 5 more positions showing how crunched my opponent's board was by the time I got close to the full bear in process. I took the latter 5 positions from the first 5 games I played out so it wouldn't seem like I was hand selecting the best to prove the point of my play. When someone finally puts out a book on backgames it will be very enlightening.

That's right, we started off by breaking up our 6 prime and now I go one step further and I break my 5 prime! This is what Falafel would call real backgammon.
is eXtremeGammon

score: 3
pip: 234
11 point match
pip: 140
score: 9

is Player 1
XGID=-abbcBBBBBaAAAba-B-a--a-a-:1:1:1:64:9:3:0:11:10
to play 64
1.XG Roller++11/1* eq: +0.129
Player:
Opponent:		60.23% (G:39.05% B:3.25%)
39.77% (G:5.43% B:0.29%)
2.XG Roller++17/11 5/1* eq: +0.113 (-0.016)
Player:
Opponent:		59.82% (G:37.85% B:2.90%)
40.18% (G:6.00% B:0.34%)
is Player 2

score: 3
pip: 215
11 point match
pip: 173
score: 9

is Player 1
XGID=-a-eaBBBBCa-----ab-abaAAAA:1:1:1:51:9:3:0:11:10
to play 51
1.XG Roller++Bar/24 9/4* eq: +0.548
Player:
Opponent:		78.86% (G:57.84% B:8.72%)
21.14% (G:2.17% B:0.07%)
2.XG Roller++Bar/24 23/18eq: +0.543 (-0.005)
Player:
Opponent:		78.65% (G:52.04% B:4.70%)
21.35% (G:2.16% B:0.10%)
3.XG Roller++Bar/19* eq: +0.511 (-0.036)
Player:
Opponent:		77.11% (G:55.77% B:6.59%)
22.89% (G:2.27% B:0.08%)

Not ideal. I certainly wish he would have cracked more before I was due to bear in. Now I have little hope of ruining his timing or crunching his board more than it already is.
is eXtremeGammon

score: 3
pip: 192
11 point match
pip: 99
score: 9

is Player 1
XGID=-AbbcCCCC-Ba--------bbb-a-:1:1:1:41:9:3:0:11:10
to play 41

A perfect result. My opponent entered with only a 63 on his first shake and from there I was able to close my points quickly and stick all his men on the 22pt. This is one great variation I hope to achieve with my initial play. (esp. at other scores where gammons and backgammons count)
is eXtremeGammon

score: 3
pip: 211
11 point match
pip: 59
score: 9

is Player 1
XGID=aBDfCBC--A----b---abb-a---:1:1:1:32:9:3:0:11:10
to play 32

Another great game for me. This time he fanned on the first sequence allowing me to close out all those checkers. The only reason he's in at all now is that he just rolled double 3s from the bar.
is eXtremeGammon

score: 3
pip: 212
11 point match
pip: 68
score: 9

is Player 1
XGID=-BBgCDC-----A-c----bb-a---:1:1:1:62:9:3:0:11:10
to play 62

It was going okay until this double four. With any luck I may get another crack or two out of him before he's able to escape a checker. (or maybe he'll roll the double 4s this time!)
is eXtremeGammon

score: 3
pip: 230
11 point match
pip: 89
score: 9

is Player 1
XGID=-AdeCBCBBB---------ad--a--:1:1:1:44:9:3:0:11:10
to play 44

I made no error according to XGr+ over .010 in arriving at this position. It's a mixed bag because I'll have some issues bearing in and my opponent will be able to hold what timing he has by flooding the outfield. It will take some real work for him to put his position back together even with the 3 checkers on his ace and deuce point they really aren't dead yet. I remain a 2-1 favorite but not what I was after from the outset for sure.
is eXtremeGammon

score: 3
pip: 268
11 point match
pip: 106
score: 9

is Player 1
XGID=--dceDCBBBB------------ba-:1:1:1:31:9:3:0:11:10
to play 31

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