Most of baseball’s managers harmed their teams when ordering non-pitchers to lay down bunts last season.
Only 13 of 30 Major League Baseball managers improved their teams’ chances of winning with sacrifice bunt attempts, according to an analysis of information from the Baseball-Reference.com Play Index.
The other 17 managers would have been better off letting their batters swing away.
In the 2013 season, the managers and teams that were best at bunting — both the decision to try a bunt and the execution of a bunt attempt — were Terry Francona of the Indians, Joe Girardi of the Yankees and Ron Roenicke of the Brewers. The managers who made the worst bunting decisions were John Gibbons of the Blue Jays, Mike Redmond of the Marlins and Walt Weiss of the Rockies.
The most profitable bunts occurred when the batter reached base, either by beating out the throw or when the defensive team committed an error. Bunts also made a positive difference in win probability when they advanced runners from first and second to second and third with no outs.
For example, Juan Centeno substantially improved the Mets’ chances of winning on Sept. 29, 2013, when he bunted in front of home with a runner on first and no outs in the bottom of the 8th. The runner, Juan Lagares, came all the way around to score, tying the game at 2. The Mets went on to defeat the Brewers 3-2. With a win probability added of 0.37, that play had the highest WPA of any sacrifice bunt attempt in the 2013 season.
The least useful bunt attempt happened when the Marlins’ Rob Brantley hit a popup to third that turned into a double play at first when Donovan Solano was caught off the bag. That play significantly reduced the Marlins’ chances of winning with a WPA of -0.27, and one strikeout by Craig Kimbrel later, the Braves notched a 3-2 victory on April 9, 2013.
This study excluded pitchers in order to compare National League and American League teams.
Sacrifice bunt attempts are one of the more easily measurable decisions that managers make, but of course this ranking shouldn’t be used to solely determine whether one manager is better than another. Many other managerial decisions include bullpen management, lineup configuration, intentional walks, stolen bases, training, scouting, preparation and intangibles, such as player motivation.
There was a low to moderate correlation between the number of sacrifice bunt attempts and their win probability added. The correlation was about 0.38.