Ali - superbackgame

The positions that follow are from one game of my match against Ali.  I lead 1 away 3 away Crawford so the checker play is essentially DMP.

I don't have much experience with superbackgames, and it shows.  Superbackgame are where you have 3 or more points in your opponent's board.  Compare to the normal backgame where you own 2 points.

These are difficult to play (for both sides) because of the complicated timing issues.  From the backgamers point of view, to win you need:

• to assemble a good front position (prime or board)
• hold it without cracking
• hit a shot
• contain the hit checker

So how the heck do you do this with six (or more) checkers back?

For example, if you have six checkers back and a four prime on your of the board that leaves you only one spare checker to play.

Here are some initial thoughts, subject to change as I learn more.

1) Being able to spring back men for timing is crucial.

• So you don't want to get primed.
• You want extra men at your front anchor ready to jump.

2) Keep pure at all times

• Never ever bury or kill checkers if you can avoid it
• Build your points in order.  Your material for offense is limited and must be used efficently.
• Place checkers where you want them.  Don't worry about the blot count.

3) When to abandon the 3rd anchor?  meaning when to switch to 2 anchor backgame?  No easy answers.

• If your timing is already busted, never abandon the 3rd anchor
• If it looks like the 3 anchor game won't work, it might make sense to get off that 3rd anchor right away and fall back on a superior 2 anchor normal backgame.

4) Think real hard before you hit that first shot!!

• Is your front game in order?  If not, you are probably better off waiting.  Be patient and trust the backgame will yield more shots later when you are ready to contain

If yes, go for it.  But with six guys back you will have a lot of work to do before you can ever recube.  That is, based on containment alone. 

The real reason to hit may be the enter and crack numbers.  If opponent enters and exposes a second blot that can spell instant doom.  You are probably looking at a double or possibly triple shot at a second blot.  This is a best case senario I think.

5) Never hit the opponent on a non-key point.

• It is probably OK, maybe even essential to hit if you can when opponent is threatening to extend the prime.  Meaning you have 3 men on your front most anchor and opponent has the back of the prime slotted.  Then you hit, absolutely.  You need to prevent him hemming you in and you need to escape to keep some pips to play.

• In almost all other cases, it is probably wrong to hit.  The reason is with 3 back anchors you are not going to win going forward.  So there is no upside to hitting.  Most likely all that happens is advance your front game too fast and crash - exactly what your opponent is dreaming for and simultaneously your worst nightmare!

• The only exception I can think of is if you a real shot at counterpriming.  This seems extremely unlikey.  I suppose if this was possible you are not really playing a superbackgame since the opponent will have some checkers back too - it's probably more accurately a prime versus prime for this strategem to work.

6) When you abandon the 3rd anchor, abandon from the front.  You need contact, so keep your backmost point.

7) If your front game does crash ...

• Don't make the deep points unless you have to
• Consider clearing six/five points with aces and dueces.  Idea is to kill sixes and fives so you crash in slow motion.  Hold what offense you have for a longer time.

8) Only do the kamikaze play if you have no choice!! 

Meaning if your game is screwed anyway, then you risk going from sucks to sucks worse (not much cost) while the upside of repairing your timing via recycling could be large.  Small risk with potential for reward, then OK go for the kamikaze play.


With the above in mind, here are some positions.


*************
32 to play.

is Ali score: 4 pip: 131

7 point match Crawford

pip: 204 score: 6 is Bill

XGID=---A-BCa----bCa-bbbcbBB-B-:0:0:1:32:6:4:1:7:10

to play 32

1.	Rollout1	13/10 6/4	eq: -0.292
	Player: Opponent: 37.70% (G:4.50% B:0.47%) 62.30% (G:33.42% B:1.45%) Conf.: ± 0.008 (-0.300...-0.284) - [100.0%] Duration: 8 minutes 07 seconds
2.	Rollout1	24/21 13/11	eq: -0.361 (-0.069)
	Player: Opponent: 34.01% (G:4.51% B:0.44%) 65.99% (G:36.89% B:1.14%) Conf.: ± 0.011 (-0.373...-0.350) - [0.0%] Duration: 11 minutes 46 seconds
3.	XG Roller+	13/8	eq: -0.331 (-0.038)
	Player: Opponent: 36.77% (G:4.99% B:0.23%) 63.23% (G:29.82% B:2.51%)
4.	XG Roller+	13/11 6/3	eq: -0.331 (-0.039)
	Player: Opponent: 36.71% (G:5.10% B:0.23%) 63.29% (G:29.58% B:2.47%)
5.	XG Roller+	13/11 13/10	eq: -0.334 (-0.042)
	Player: Opponent: 36.90% (G:4.85% B:0.23%) 63.10% (G:30.94% B:2.76%)
1 1296 Games rolled with Variance Reduction. Moves: 3-ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.02, MET: Kazaross XG2

I am behind a 5-prime already, so the timing is precarious. Basically my timing is screwed.

I jumped with 24/21, 13/11. By moving a spare to the 4 point I hope to transition to a reasonable 34 game. I can escape with sixes and don't really care about being hit.

The computer likes 13/10, 6/4. Themes. Make the points in order. Who cares about blots. When timing sucks, never abandon the 3rd anchor. When I am forced to break eventually, abandon from the front. (Vacate the 4 point and hope to have a 13 game. Keep your rearmost anchor)

Note the other plays all retain the three anchors.

*************

I have 22 to play from the air.

is Ali score: 4 pip: 122

7 point match Crawford

pip: 213 score: 6 is Bill

XGID=---A-BC----a-BbabbbcbCB-AA:0:0:1:22:6:4:1:7:10

to play 22

1.	XG Roller++	Bar/23 6/4(3)	eq: -0.382
	Player: Opponent: 33.93% (G:5.18% B:0.22%) 66.07% (G:38.00% B:2.06%)
2.	XG Roller++	Bar/23 6/4(2) 5/3	eq: -0.389 (-0.007)
	Player: Opponent: 33.93% (G:5.05% B:0.23%) 66.07% (G:39.60% B:2.36%)
3.	XG Roller++	Bar/23 13/11* 11/9 6/4	eq: -0.440 (-0.057)
	Player: Opponent: 32.29% (G:4.55% B:0.18%) 67.71% (G:40.93% B:3.19%)
4.	XG Roller+	Bar/21 24/22 6/4	eq: -0.396 (-0.014)
	Player: Opponent: 32.50% (G:4.68% B:0.19%) 67.50% (G:40.42% B:1.29%)
5.	XG Roller+	Bar/23 6/4 6/2	eq: -0.415 (-0.033)
	Player: Opponent: 33.47% (G:4.23% B:0.21%) 66.53% (G:43.54% B:3.10%)

eXtreme Gammon Version: 2.02, MET: Kazaross XG2

I played Bar/23, 13/11*, 11/9, 6/4.

This play at least has the merits of putting the checkers where you want 'em. But am I really going to win going forward? Hell no. I've got enough back already so I don't need any desperate kamikaze play to gain more timing. I am violating rule #5 (never hit on a non-key point).

The computer likes Bar/23, 6/4(3).  Themes.

Stay as far back as possible.  Never hit.  Kill big numbers in your inner board.

***************

41 to play from the bar.

is Ali score: 4 pip: 129

7 point match Crawford

pip: 227 score: 6 is Bill

XGID=---aABB--A---AabbbbcbCBAAA:0:0:1:41:6:4:1:7:10

to play 41

1.	XG Roller++	Bar/21 24/23	eq: -0.293
	Player: Opponent: 39.20% (G:6.06% B:0.17%) 60.80% (G:38.90% B:2.81%)
2.	XG Roller++	Bar/24 13/9	eq: -0.326 (-0.033)
	Player: Opponent: 39.03% (G:4.56% B:0.16%) 60.97% (G:37.19% B:4.30%)
3.	XG Roller+	Bar/21 22/21	eq: -0.699 (-0.406)
	Player: Opponent: 23.56% (G:2.53% B:0.08%) 76.44% (G:58.53% B:6.90%)

eXtreme Gammon Version: 2.02, MET: Kazaross XG2

I played Bar/24, 13/9. Not a huge error.

But I can make a superior 3 anchor game with Bar/21, 24/23. I make 3 anchor in a row which is strong. I have two spared at the edge already which is good. By leaving the ace open - even though I abandon the rearmost anchor this looks like an exception. I establish the ace-point suction. So Ali eventually will eventually move lots of checkers to the ace.

***************

33 to play

is Ali score: 4 pip: 121

7 point match Crawford

pip: 222 score: 6 is Bill

XGID=---aABB--B-----abcbccCBAB-:0:0:1:33:6:4:1:7:10

to play 33

1.	XG Roller++	9/6 9/3* 5/2	eq: -0.418
	Player: Opponent: 36.38% (G:3.03% B:0.08%) 63.62% (G:41.59% B:6.11%)
2.	XG Roller++	9/3* 6/3 5/2	eq: -0.421 (-0.003)
	Player: Opponent: 37.07% (G:2.90% B:0.07%) 62.93% (G:41.34% B:6.93%)
3.	XG Roller++	24/21 9/6 9/3*	eq: -0.485 (-0.067)
	Player: Opponent: 30.62% (G:3.88% B:0.14%) 69.38% (G:46.13% B:3.67%)
4.	XG Roller+	9/3*(2)	eq: -0.430 (-0.012)
	Player: Opponent: 33.75% (G:3.66% B:0.15%) 66.25% (G:40.19% B:4.17%)

eXtreme Gammon Version: 2.02, MET: Kazaross XG2

Not a good shake.

I left two inner board blots with Bar/21, 9/6, 9/3*

Two kamikaze plays are superior. Both leave four inner board blots in a gambit to repair the timing.

**************

41 to play.

is Ali score: 4 pip: 84

7 point match Crawford

pip: 191 score: 6 is Bill

XGID=-BB-B---------AAAabfeBBBa-:0:0:1:41:6:4:1:7:10

to play 41

1.	XG Roller++	15/11 14/13	eq: -0.156
	Player: Opponent: 45.69% (G:4.04% B:0.08%) 54.31% (G:32.66% B:2.63%)
2.	XG Roller++	16/12 15/14	eq: -0.173 (-0.016)
	Player: Opponent: 44.90% (G:4.29% B:0.08%) 55.10% (G:32.89% B:2.66%)
3.	XG Roller++	21/17* 16/15	eq: -0.255 (-0.099)
	Player: Opponent: 40.78% (G:4.90% B:0.08%) 59.22% (G:32.94% B:2.65%)
4.	XG Roller+	15/10	eq: -0.181 (-0.024)
	Player: Opponent: 44.76% (G:3.37% B:0.09%) 55.24% (G:33.79% B:2.89%)
5.	XG Roller+	16/11	eq: -0.187 (-0.030)
	Player: Opponent: 44.41% (G:3.54% B:0.09%) 55.59% (G:33.76% B:2.84%)
6.	XG Roller+	16/12 14/13	eq: -0.187 (-0.031)
	Player: Opponent: 44.41% (G:3.14% B:0.08%) 55.59% (G:33.85% B:2.85%)

eXtreme Gammon Version: 2.02, MET: Kazaross XG2

I hit with 21/17*, 16/15 violating rule #4 - Think real hard before you hit that first shot!!

My front game is no where near ready.  Any play which moves the outfield men is reasonable.  I would ideally like to remake the six point before hitting.  I still hold three anchors and more shots should be forthcoming.  Patience grasshopper!!


Next post we get to the last game of this match, another backgame.