Opening Rolls

Forum Archive : Opening Rolls

Opening 43: In GOL online match

From:   Raccoon
Date:   23 February 2004
Subject:   I'm ok, you're ok with opening 43
Forum:   GammOnLine

Sometimes it's hard to keep up with the latest, which turns out to be
the oldest.

"I used to play 13/10 13/9," says the Aspiring Novice. "That's what
Magriel recommended. That old book! But then I heard that 24/20 13/9
was just as good, and then I heard that it was even better in
rollouts, so that's what I play now."

"Oh, no," says Eddie Expert, "the latest greatest rollouts show that
there's an even better splitting play -- 24/21 13/9. No expert has
played 24/20 13/10 for years."

"Really? Ok, I'll try it!"

"Oh, no," says Eddie, "now we all play two checkers down. Seems
Magriel was right about that one."

Course, some of the experts never switched, nor do they all agree with
Eddie. And actually, Magriel expressed "no strong preference" between
the recommended 13/10 13/9 and the "alternate" play 24/20 13/10 (no
mention of 24/21 13/9).

This is the 5th opening 43 in 18 on-line matches.

Match 1, Game 6, Readers behind 7-away 5-away play 24/21 13/9.
  Kit comments: "In the expected three-horse race, 24/21, 13/9 came
  through as the clear favorite. This was sort of a surprise to me. I
  had no idea that this opening 4-3 had gained such popularity. Of
  course any of the three choices are fine, and they are probably all
  about equal. My usual preference is 13/10, 13/9 since if nothing bad
  happens it is hard not to be able to build a useful point next turn.
  Behind in the match as Blue is here, I believe that bringing the
  builders down is even clearer. This tends to lead to more gammonish
  positions, since White is unable to split his back men and go after
  an advanced anchor."

Match 10, Game 3, Kit ahead 3-away 9-away plays 24/20 13/10
  Kit comments: "At the match score I believe it is clear for me to
  split rather than bring the builders down with 13/10, 13/9. I want
  to avoid double-edged gammonish positions, since I can't use the
  full four points from a doubled gaammon but Blue can. I prefer
  splitting, which is more likely to lead to a holding game type of
  position with less of a gammon threat. If I can grab an advanced
  anchor, the gammon danger goes way down. If I were behind 8 to 2,
  then I would definitely play 13/10, 13/9. This would make it
  different for my opponent to split his back checkers safely, so he
  couldn't get an advanced anchor."

Match 14, Game 1, Kit plays 13/10, 13/9, without comment.

Match 14, Game 4, nine-away all, Readers play 24/20 13/9.
  Kit comments: "The splitters have it. By a lot. About 80% of the
  readers voted for one of the splits. My personal preference is still
  13/10, 13/9, but of course both of the splitting plays are fine.
  24/20, 13/10 goes after the best anchor. 24/21, 13/9 brings down a
  slightly more potent builder. Between the splitting plays I have
  always preferred 24/20, 13/10 -- no special reason; it just feels
  better to me."

Match 17, Game 6, Kit behind 10-away 7-away plays 13/10 13/9.
  Kit comments: "At the match score this is clearly my best way to
  play an opening 4-3, since it leads to sharper positions. If the
  score were reversed, a splitting play would be more attractive."

John O'Hagan  writes:

All 3 plays are close. Two men down gives the opponent a chance to
make a pretty big error if he rolls 51,41, or 21. He's definitely
supposed to slot with any of these, but lots of players (not including
Kit) don't know this.

Between the 2 splits, I've always kind of preferred 13-9 24-21. The
builder on the 9 point is better than on the 10 so you get more point
making rolls. Also consider the situation after a POH roll. Splitting
to the 21 is clearly better here for two reasons: 1. The 5 point is
inherently stronger than the 4 point. 2. If you split to the 4 point
and get pointed on, you will have a good 4 to play (covering the 9
point). But split to the 5 point and get pointed on and your 5's don't
play very well.

The one big advantage of playing 24-20 13-10 is that the 20 point
holding game plays better than the 21 point.

Gregg Cattanach  writes:

I've become a fan of 13/9 13/10 (for money), because if you are
missed, all 36 rolls make a constructive point on your side of the

Here's the long Snowie rollout data: (these are 25920 games, precise

                   $$      DMP      GS     GG
4-3 13/9 13/10   .008    -.005   -.289   .306
    24/20 13/10  .004    -.001   -.272   .278
    24/21 13/9   .003    -.003   -.277   .282
    24/20 24/21 -.006    -.001   -.263   .249

Marty Storer  writes:

Used to be that 13/9 24/21 would draw lots of errors even against
reasonable players. Used to also be that 13/9 13/10 fared extremely
well against missing numbers, better than would be expected today when
most decent players reply with, for example, 52: 13/8 24/22, versus
old-style 13/8 13/11 or 13/8 6/4. At one time the biggest split, 24/20
13/10 was thought to give best balance, and just about everybody
played it.

Recently I opened 43: 13/9 24/21 against someone rated, like, 1650 on
FIBS (0-0 to 5). Splitting to 21 point is a very good tester against
an unknown or an assumed weaker player.

Opponent replied 32: 13/8. I fully expected 6/4*/1* which is probably
the best practical choice given the matchup. I can't strategize much
when both of me are on the bar. But 13/8? What a dividend.

What are some bad replies to 43: 13/9 13/10? Money play or equivalent,
that is. I split to the 22 with the 52 and 32 replies. Alternatives
with 32 aren't bad: slot 4, or two builders. I think 52: 13/8 13/11 is
worse than 13/8 6/4. Maybe someone will occasionally reply 64: 8/2
6/2, antithematically. But other than that, there's not much hope of
anything too weak. You can argue about replies that slot the 5 point,
but there's not much difference between slotting say with 21: 13/11
6/5 (vs. 13/11 24/23), and a weaker player ought to split.

Against 43: 13/9 24/21, opponent can refuse to hit loose, or can hit
twice wrongly with 52: 6/1* 6/4* or 54: 6/1* 8/4* (admittedly those
double hits are bizarre and only the Iceman-like are likely to try
them). Refusal to hit loose is usually quite wrong. People who aren't
eager to hit loose against major splits are more likely to hit on the
5 point than the 4.

Two up, 43: 24/20 24/21, will draw some errors, but only against
clearly weaker players will you see refusal to hit loose. The game
tends to get one-dimensional: you want to escape or anchor. Having
advanced both back checkers to target points, you have to do something
with them ASAP. A one-dimensional plan isn't usually the best for
inducing mistakes.

Against clearly weaker players, what I like least about 43: 13/9 13/10
is the 11 hitting numbers (including double 2 and double 3, with which
a weaker player doesn't do very badly to hit). Weaker player hits,
follows up with good throw or two, then may easily be able to play
from there. Of course, if weaker opponent doesn't hit, you have good
blocking chances, and your superior skill will count in a game
involving blocking, especially where you have a better position.

In most situations, I play either 13/9 24/21 or 13/9 13/10, often on a
whim. Either play has many good justifications, theoretical and
practical. I think that serious study of third-ply plays (replies to
replies), and early cube decisions, will pay off quite a bit,
especially for opening rolls like 43, with competing themes at
different score situations and against different types of opponents.
Did you find the information in this article useful?          

Do you have any comments you'd like to add?     


Opening Rolls

At different match scores  (Louis Nardy Pillards, July 2002) 
Average advantage of winning opening roll  (Chuck Bower, Oct 1998) 
Choosing a strategy  (Daniel Murphy, June 2001) 
Early game rule of thumb  (Rich Munitz, Feb 2009) 
Factors to consider  (Kit Woolsey, July 1994) 
How computers play  (Kit Woolsey, Mar 1995)  [Recommended reading]
Magriel's Chapter 5  (Hayden Alfano+, May 2006)  [Long message]
Mloner vs Jellyfish  (Kit Woolsey, Dec 1995) 
Nactating a whole game  (Nack Ballard+, Jan 2011)  [Long message]
Nactation  (Jim Stutz+, June 2010) 
Nactation overview  (Nack Ballard, Oct 2009) 
Nactation--Why use it?  (leobueno+, Jan 2011) 
Opening 1's: Split or slot?  (Douglas Zare, Dec 2003) 
Opening 21: Rollout  (Stick, Mar 2006)  [GammOnLine forum]
Opening 21: Split or slot?  (Dick Adams+, Dec 2003) 
Opening 32: Rollout  (Stick, Feb 2006)  [GammOnLine forum]
Opening 43: In GOL online match  (Raccoon+, Feb 2004)  [GammOnLine forum]
Opening 43: Pros and cons  (Stick+, Jan 2006)  [GammOnLine forum]
Opening 43: Which split is better?  (Peter Backgren+, Aug 2000) 
Opening 43: Which split is better?  (Michael J. Zehr+, Mar 1996) 
Opening 51: Rollout  (Stick, Feb 2006)  [GammOnLine forum]
Opening 52: Merits of splitting  (Peter Bell, Apr 1995) 
Opening 53: Magriel's recommendation  (George Parker+, July 1997)  [Long message]
Opening 53: Split to 21?  (Alex Zamanian, Aug 2000) 
Opening 53: Why make the three point?  (Kit Woolsey+, Feb 1996) 
Opening 6's: Slot the bar point?  (Chuck Bower+, Feb 2000) 
Opening 6's: Slot the bar point?  (David Montgomery, June 1995) 
Opening 62: Could running be best?  (Gary Wong, Sept 1997) 
Opening 62: Split, run, or slot?  (Chuck Bower, May 1997) 
Opening 63: Middle Eastern split?  (Mark+, Apr 2002) 
Opening 63: Slot the four point?  (Dennis Cartwright+, Mar 2002) 
Opening 64: Make the two point?  (William Hill+, Jan 1998) 
Opening 64: Make the two point?  (Darse Billings, Feb 1995) 
Opening 64: Rollout  (Peter Grotrian, Jan 2006)  [GammOnLine forum]
Opening 64: Split to 20?  (Peter Bell, June 1995) 
Opening 64: Three choices  (Brian Sheppard, July 1997) 
Opening 65: Becker on lover's leap  (Jeffrey Spiegler+, Aug 1991) 
Opening 65: Computer rankings  (Chuck Bower, Jan 1997) 
Opening rolls ranked  (Arthur+, Apr 2005) 
Rollouts of opening 21 and replies  (Alexander Nitschke, Oct 1997) 
Rollouts of openings  (Tom Keith+, Jan 2006) 
Rollouts: Expert Backgammon  (Tom Fahland, Aug 1994) 
Rollouts: Jellyfish 3.0  (Midas+, Sept 1997) 
Rollouts: Jellyfish 3.0 level 6  (Chuck Bower, Feb 1999)  [Recommended reading]
Rollouts: Snowie 4.1  (Rene Cerutti, Apr 2004) 
Slotting the four point  (Joe Loria+, Oct 1999) 
Snowie's openers and replies  (rcerutti, Feb 1999)  [Long message]
Splitting versus building  (Dave Slayton+, Aug 2000) 
Splitting versus slotting  (Daniel Murphy, Apr 2001) 
Splitting versus slotting  (Daniel Murphy, Sept 1997) 
Trice's rankings  (Marty Storer, Feb 1992) 

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