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Blitz or Consolidate?

Aug 1, 2022 | Backgammon Problems: Blitzes, Uncategorized

Cash game. Black owns the cube. White on move.

White to play 3-3.

White’s off to a good start in this position. He’s already made a three-point board, whereas Black hasn’t yet made a new point, and White has hit a blot, leaving him 17 pips ahead in the race. Black, meanwhile, is still scrambling to make an anchor. Last turn White offered an aggressive double, and Black quite reasonably took.

Now White throws one of his best shots, 3-3, and has three game plans:

(a) The consolidation play with 14/8 13/10(2), leaving him firmly in control with a nice edge, or

(b) Consolidation plus a little attack with 24/21 14/8 6/3*, or

What’s the right idea?

Here’s the general approach for handling these sorts of positions. If your opponent has no structure, and the cube has already been turned (activating gammons), then the blitz dominates any safe game plan. If the blitz fails, White can just drop back into some sort of holding game where he holds a slight edge. If White makes one of the solid plays, he’ll reach those holding games anyway since almost all of Black’s rolls will anchor somewhere. White will be slightly better off if he goes for the holding game right away, because of his racing lead, but the difference is small. But if the blitz succeeds White wins a gammon, and with the cube already turned that’s a quick four points and a huge swing.

As Black acquires more structure, the blitz drops in value. If we alter Black’s position and give him his 5-point (as though he had rolled a 3-1 at some time), then the blitz plays are only slightly superior to the consolidating plays. If we give Black two extra points, say the 5-point and the 3-point, then the blitz plays become pretty big errors and the consolidating plays becomes correct. (There’s very little difference between Play (a) and Play (b) no matter what structure Black has.)

So we’re blitzing. Next question: what’s the right way to blitz?

What makes this problem especially interesting is that White has two distinct ways to blitz: the obvious 13/4*/1* and the obviously riskier 13/4* 6/3*. Problems with two plausible blitzing moves are rare, but we can choose between them by noticing that the double-hit with 13/4*/1* exposes only one blot in the board, and a hit may only allow Black to get an ace-point game later. If White hits on the 3-point and 4-point with two checkers and Black then throws a three or four, he may get a good anchor quickly. The two blitzing plays are close (and far superior to the non-blitzing plays) but the play that exposes only one inside blot is slightly better.

Where to Leave Blots

Jul 14, 2022 | Backgammon Problems: Middle Game

Both positions: Cash game. Center cube. White on move.

(a) White to play 5-4.

(b) White to play 6-2.

In Problem 140A, White has no way to safety the blot on his 16-point. In fact, he can’t avoid creating a second blot as well. He has a few reasonable plays: 13/4, 16/11 13/9, 16/11 6/2, 13/8 13/9, and 6/1* 13/9. None of these plays look terribly strong. How should he decide among them?

Bearing In Against the Ace-Point

Jul 1, 2022 | Backgammon Problems: Ace and Deuce-Point Games

Cash game. Black owns the cube. White on move.

White to play 5-1.

When bearing in against an ace-point or other low anchor game, you generally have two goals in mind. The first is safety; you want to create formations that are less likely to leave blots as you bear off. The second is winning a gammon; you’d like to maximize your chances of winning a gammon if you can.

Split or Run?

Jun 15, 2022 | Backgammon Problems: Early Game

Cash game. Center cube. White on move.

White to play 5-2

The early part of a backgammon game is dominated by two key goals: hit blots and make points. The easy moves are the ones where you can only do one good thing. The hard moves are those where you can do two good things, and you have to make a tough choice, or no really good things, and you have to decide how best to arrange your checkers for future action.

This position is an example of the latter situation. White can’t make any points with a 5-2 roll, and his only hit, 6/1*, doesn’t accomplish anything good. So he has to shuffle his checkers around somehow and get ready for action next turn.

My cardinal rule in these positions comes from the medical profession: “First, do no harm.” In backgammon terms, that means don’t try plays that make your distribution worse rather than better. Here, I’ll reject 13/8 for just that reason. After 13/8, White has gone from a nice position with a spare on both the 13-point and 8-point to a position with a small stack on the 8-point and no spares on the midpoint. That’s not an improvement, so let’s reject all the plays involving 13/8.

Since we’ve already rejected the awful 6/1*, we’re now left with just two candidates: 23/18 13/11 and 23/16. Running all the way out and trying to escape with 23/16 is the safer play: fewer ways to get hit and fewer blots. Since Black has a better board right now, extra safety is not a bad idea.

The alternative, 23/18 13/11, tries for a bit more. White creates a new blot and exposes himself to more hits in return for a chance to make a great anchor on Black’s bar-point. The problem with the move is a bit subtle. The purpose of the new blot on the 11-point is to give White some extra chances to make his 5-point with rolls like 6-3 and 6-1. However, White won’t have a chance to execute those threats because he’ll most likely be on the bar next turn. Black is going to hit on his bar-point with all his ones and sixes, and he will probably hit on his ace-point with fives as well. In fact, Black’s only non-hitting numbers are 4-3 and 4-4, and 4-3 actually makes White’s 5-point, rendering the blot on the 11-point somewhat useless!

Here’s a quick rule of thumb: a move like 13/11 is excellent when you have an anchor somewhere, so the blot on the 11-point is a useful builder immediately. It’s not so useful when a hitting contest is about to ensue on the other side of the board. As long as the battle for Black’s bar-point is unresolved, a blot on the 11-point is really just an extra target. Play the simple 23/16 instead and try to escape a checker.

Improving Your Technique

Jun 1, 2022 | Backgammon Problems: Middle Game, Uncategorized

Cash game. Center cube. White on move.

White to play 2-2.

The advent of the bots in the late 1990s enabled players to solve a myriad of small technical plays that recurred frequently but couldn’t really be tackled with hand rollouts or pure reasoning. Hand rollouts were so slow that they really had to be reserved for positions where the solution was unknown but the difference between plays was likely to be large and important. Players ignored what appeared to be small technical stuff, on the theory that solving these problems, even if possible, was most likely a huge waste of energy.

Creating Mobility

May 15, 2022 | Backgammon Problems: Middle Game, Uncategorized

Cash game. Center cube. White on move.

White to play 6-4.

This is a comparatively easy problem if you can properly balance the key features of the position. Let’s step back for a second and look at just what is happening, before we try to evaluate the different choices.

The race: White will trail in the race by 16 pips after he plays his 6-4. Considering that he has five men back to Black’s two, he’s not as far behind as one might think at first glance. Since he’s trailing in the race, however, he wants to maintain a good anchor (to generate some shots) and a good blockade (to contain blots he may hit).

Blockades: White has four good points in front of Black’s anchor. That’s a solid plus for him, if he can maintain it. Black has a motley collection of scattered points, which indicates that he probably won’t be able to build a good block anytime soon, and that he’ll likely have to start leaving shots in the near future.

Weaknesses: For White, what might seem a strength is actually a long-term weakness. He has two great anchors, on the 20-point and the 18-point, but that’s one great anchor too many. The 20-point/18-point combination doesn’t work well together; they tie up 76 pips at a time when maneuvering freely is still key.

Black’s weakness is glaringly obvious; it’s the 2-point, too deep in his board to be useful at this stage. Black might have had good reason to make it in the past, but now he’d be better off if those checkers were back on the 4-point or the 9-point.

Now let’s put all this together and see just what we can do with the 6-4.

8/2 6/2. A bad choice. White burns two of his remaining builders to make a useless point far behind Black’s anchor. Now all his remaining points are stripped and his only convenient rolls next turn are those that can be made entirely with the blot on the 24-point. Take a look at how numbers like 4-1, 3-2, 6-1, 5-2, 4-3, 5-1, and 6-4 play next turn. In complex middle games with action on both sides of the board you need checkers that can move easily, and sometimes you have to take risks to preserve those checkers.

24/18 6/2 and 24/20 8/2. Not as committal as making the 2-point, but half-hearted versions of the same idea. You only have 15 checkers, and you want everyone in play at this stage of the game.

20/10. To those who worship the 5-point, this looks like a shocking idea. White breaks the defensive 5-point before he must. But it’s really a fine move, which solves all White’s problems at once. White doesn’t need both anchors, so he gives one up voluntarily.

Take a look at the position after 20/10 and notice how White has solved most of his problems. He now has five spare checkers, ensuring that he won’t have to concede any valuable points in the near future. He’s got more combinations to make his 5-point or 7-point, as well as more ways to attack if Black should split his back checkers for some reason. Finally, he’s resolved the issue of too many anchors in a neat and efficient fashion.

If you missed this problem, it’s probably because you’re too focused on static features of the position, and not enough on the flow of the game. Try to anticipate how the game is likely to develop over the next couple of rolls, and avoid positions where you have a real shortage of checkers that can move.