This article originally appeared in the December 1999 issue of GammOnLine.|
Thank you to Kit Woolsey for his kind permission to reproduce it here.
We have all heard plenty of discussion about the importance of timing when
you or your opponent is playing a potential back game. But what is timing
anyway? To get a feel for things, let's look at the following two positions:
Meanwhile, what about Blue's position. Blue will have to keep playing. If Blue is able to maintain a strong board, he will have quite decent winning chances. After he hits a shot, he can contain the checker and possibly force White to jar another checker loose. This should give Blue a game-winning redouble in the ideal scenario. On the other hand, if Blue is forced to crunch his board things aren't so good. Now when Blue hits a shot it will be difficult to contain the hit checker, and it will be impossible to force White to expose a second blot. Also if Blue is prematurely squeezed off one of the anchors in order to maintain his board Blue's chances of hitting a shot go down considerably. It will be easier for White to play safely, and even if White if forced to leave a shot it may only be a single shot rather than a double shot.
Will Blue be able to hold the fort? It is close. In the first position, Blue has two checkers on the midpoint to play with. These checkers can absorb a couple of large rolls without destroying Blue's position. Eventually Blue will spring the spare checker on the 22 point, and that will probably be sufficient to give Blue time to maintain his board when while waiting for his shot.
In the second position, it is another story. Blue doesn't have those two checkers on the midpoint. If Blue doesn't roll a six to spring a back checker, he will be forced to play his fours and fives deep into his home board. Even if Blue does roll an early six, he will probably soon run out of time and have to either crunch his board or release one of the anchors. Either way, his winning chances go down considerably.
How are these positions reached? When one side is playing a back game or a potential back game, there is a lot of jockeying around before things settle down. Unless the front game player has a full prime, the player playing the back game has the potential to win frontwards. He will try to build up a board as efficiently as possible, so that he can go frontwards if things go well. His opponent will have the difficult decisions of whether or not to hit blots on slotted points. If he hits, this may help the timing of the back game player. Of course, the more checkers sent back the better the gammon chances are. If he doesn't hit, then the back game player may be able to switch gears and go frontwards.
If we look at the two positions, we see that the main difference is that in the first position Blue held his midpoint while in the second position he did not. Surprisingly enough, that is the key to maintaining timing while the early jockeying goes on. If you are able to keep your midpoint (or better, a point farther in your opponent's board) while he brings his checkers home, you are likely to be able to hold out. However if you break your midpoint you will find that your game often disintegrates, as your army is divided into two pieces.
It looks so natural to make the bar point. After all that is a four-prime, and we might contain White's back checker. If the remaining checker on the midpoint gets hit, perhaps we can recirculate it and improve our timing.
Well, things just don't work that way. Once the midpoint is gone, Blue simply isn't going to be able to retain his timing. If White hits the checker on the midpoint, this will hurt Blue's timing rather than help it. With nothing in the outfield to play with, Blue will have to start to crunch his home board with every four or five he rolls. As for containing White's checker and winning the priming battle, that simply isn't going to happen.
What should Blue be doing? Not clear. The natural play is 10/8, 7/3*. This retains the midpoint and drives the White checker back. If Blue is hit on the three point, that won't bother him. With the midpoint held in place, Blue really does have a chance to recirculate checkers. If White enters deep, perhaps Blue actually can contain the checker and win a priming battle. The main disadvantage with this play is that if White stays on the bar (particularly with large doubles) Blue has lost a chance to force White to play large numbers and correct Blue's shaky timing.
There are other possible approaches. One is to play something like 10/4. This forces White to play his next roll while holding the midpoint. The problem with this play is that if White escapes the back checker contact is lost, and Blue's timing is very likely to fail. Another approach, particularly at double match point where gammons don't count, is the kami-kaze play of 7/3*, 4/2. This sort of play makes it quite likely that White will be forced to hit one of Blue's advanced checkers, thus giving Blue a greater chance to recirculate and maintain his timing. Of course this sort of play will lead to getting gammoned more often, so it probably isn't correct if gammons count. However it will win a lot of games.
How far can we go to hold the midpoint? Pretty far. For example:
Don't touch those checkers on the midpoint. It isn't just a matter of not hitting. That is often a myth about back games that neither side is supposed to hit a blot. Often you can gain by hitting, when you force your opponent to do something he doesn't want to do. For example if the roll had been 6-5 then playing 22/11* would be fine. Here, however, you don't want to lose that vital midpoint. If you play 22/16, 13/11* and White enters with a hit you lose your vital outfield control and your game will probably soon fall apart.
Since White is playing a back game, it might seem right to not hit the blot and let White play his rolls. Nothing could be further from the truth. If Blue leaves the blot alone, White can use that checker to handle awkward rolls. By hitting, Blue will force White to either break the midpoint (shudder) or play deep into the inner board if White rolls fours or fives. How Blue should hit is another matter -- probably 13/10*, 10/9 slotting the edge of the prime is best. What is important is that Blue should definitely hit and attempt to split White's army into two pieces.
We all know how bad it is to dump a checker onto the ace point when playing a back game. The checker is out of play, and if we are forced to cover the blot then we lose the opportunity to build a prime to contain a hit checker and force our opponent to jar a second checker loose. However, breaking the midpoint and losing our lifeline is worse. Blue must play 24/22, 6/1. If he plays 24/22, 13/8, White has the opportunity to scoop up Blue's outfield blots, particularly the blot on the midpoint. When that blot is hit, Blue's game will crumble as soon as Blue enters from the bar. Blue simply must hang onto the midpoint. He hopes to roll a six next turn and get some breathing rooom, or that White's back checker doesn't escape and Blue can stir things up in the inner board without breaking the midpoint. Not great for Blue, but once the midpoint goes the timing will soon follow.
It might seem natural to play either 23/17, 13/10 or 22/13. However I strongly believe the proper play is 22/17, 4/1*. The idea is to go all out to make the 17 point. If Blue can snag that point, it is almost impossible for White to break Blue's timing. This will allow Blue to break his midpoint, since he will have established a new and better lifeline. In addition any checkers which are sent back will automatically have a place to jump out. Blue will even be willing to temporarily abandon the back anchor in order to nail down the 17 point. He will almost certainly be able to get it back sometime in the future, and even if he doesn't he can play comfortably from the defensive three and eight points. It is worth dumping a checker onto the ace point in order to grab the 17 point. Needless to say, White must hit the blot if at all possible.
The above positions illustrate the importance of maintaining a foothold in the outfield when playing a back game. Think about back games you have seen played, and whether or not they succeed. You will find that having that lifeline is very often the difference between success or failure of the back game. This trick of holding your midpoint when playing a back game and forcing your opponent to break his when he is playing a back game will pay off.