Do Sacrifice Bunts Really Provide an Edge?

Everyone has seen it. It's the first inning, no score. The leadoff batter reaches base, and the number two batter steps in. The first and third basemen are charging in, the batter squares and drops a bunt half-way between the plate and the mound. The pitcher scrambles for the ball, snaps a look at second and tosses the ball to the second baseman who is calmly planted on first base. The runner is out by two steps. This scene is played out in nearly every Japanese baseball game. When the leadoff hitter gets on in the first inning, everything is clear. The number two hitter's duty is to advance the leadoff runner with a bunt. The announcer's duty is to remind us that this is the way baseball is meant to be played. An analyst lectures the audience on the significance of seizing the initiative with the sacrifice bunt. The batting team, he tells us is now in control of the situation and ready to exploit their advantage.

When a team bunts in the first inning, which is very common in Japan, it is sacrificing runs. The sacrifice bunt, like the stolen base, is a one run strategy. One run strategies risk making an out in exchange for advancing a base runner. They increase (very slightly) the chances of scoring a single run, while reducing the chances of scoring a lot of runs. In order to score a lot of runs, you need to get a lot of runners on base.

A one run strategy causes fewer runs to score, because it generates outs rather than base runners. There is an enormous difference between having a runner on second with one out and having two runners with no outs. This latter situation is far more likely to lead to a big inning. If a team's best power hitters are coming to the plate, the potential for scoring three or more runs is very good. However, this increased potential of a big inning makes a one run strategy in the first inning very costly.

One study of bunts in the major leagues from 1987 to 1989 (Dewan, Zminda, et al. 1990 p.68) showed some surprising results. With no outs and a runner on first, bunts by hitters who were not batting ninth, did not increase the chances of scoring at least one run. Successful bunts in these situations did however reduce the total number of runs scored by 14%. One might expect bunts by the number two hitter to be even more damaging.

In 1992, I studied the effectiveness of sacrifices in the first inning. I looked at all cases when the lead-off runner reached first or second base. When this happened, teams scored 32% more runs when the number two hitter didn't have a successful sacrifice hit. Of the twelve teams, only the Giants and Lions scored as many runs with a bunt as they did without. The Giants scored about the same number of runs per inning, but the Lions scored more runs when the number two hitter sacrificed. I didn't do a detailed analysis of how the Lions scored their runs. I assumed at the time that they scored a lot of runs in those innings because their big hitters hit a lot of home runs.

The Lions bunt quite a lot, and they are a very successful team. The former manager of the Lions, Masaaki Mori, is famous for his devotion to the sacrifice bunt. His team's circumstances made one-run strategies very attractive. The Lions play in a pitchers' park where one run could be decisive, and they have had reliable starters who could be counted on to stifle the opposition.

I know it makes no sense, but many journalists and otherwise sensible baseball people attribute the Lions' offensive achievements to their ability to advance base runners by making outs. Well, since the media makes such a big deal out of it, and the Lions DID score more runs when bunting in the first inning in 1992, I thought it might be worth looking into.

What I want to know is this: Can sacrifice bunts provide a hidden advantage? A team COULD score more runs following a bunt purely as a result of luck. However, any result caused by luck, will disappear over time. If a sacrifice by the number two hitter does provide a real edge, then we would expect it to hold up over a period of years. If a bunt can provide an advantage, what might be causing it? One possiblity is that succeeding hitters are more productive following a successful sacrifice. Could the bunt give the next few hitters an edge?

Method

To find out if a team can score more runs via the sacrifice, I looked at 369 Seibu Lions games from 1992 to 1994. I chose Seibu's games, because they are frequently held up as the prime example of how the sacrifice wins ball games. I looked for each inning when Seibu's number one hitter led off. I noted in each case, whether a sacrifice bunt had been made or not. I also counted the number of runs scored in each inning.

If the Lions derive a benefit from the sacrifice hit, we would expect them to score more often when sacrificing and score nearly as many runs (within 5%) as when they opt not to bunt.

To analyze the performance of the cleanup hitters, I also recorded the performance of the the number three and four hitters. I chose to look at the three and four hitters, because they both typically bat when the leadoff hitter reaches base. Sometimes, either the number three hitter hit into a double play or a base runer was otherwise removed