By Jim Allen
In the last post, I mentioned how visiting NPB teams were winning more often when they bunted in the first inning with no outs and a runner on first base. Someone suggested that perhaps scoring the first run when on the road was bigger than it is at home, but prior to 2011 — when teams were able to choose very lively balls, it was the home team that benefited by bunting in the bottom of the first in scoreless games.
Starting with play-by-play data from 2003 to 2016, I noted what the first batter did in the first inning what the following hitter did, how many runs were scored, each starting pitcher’s runs allowed per nine innings that season and whether the team won or lost.
From 2003 to 2010, visiting NPB teams posted a .458 win percentage in games when they attempted a bunt in the first inning after the leadoff man reached first base via a walk, a hit batsman, a single, an error, a fielder’s choice or an uncaught swinging third strike. When faced with those situations and the No. 2 hitter’s plate appearance did not end in an attempted bunt, the visitors posted a .504 winning percentage.
From 2011, visitors bunting in the first inning had .502 winning percentages, those not bunting in the top of the first with the No. 2 hitter had a .459 figure.
For home teams it was the reverse. Before 2011, they won more often when bunting. Since 2011, they are bunting more often and costing themselves wins.