A closer look at Mickey Callaway’s bullpen use

Speaking from experience, fans love to play manager while watching games. The only thing they love more is to scream at the actual manager when he makes a contrary move. This happened Tuesday night when in Flushing skipper Mickey Callaway pulled Noah Syndergaard with two outs in the sixth inning while around the world fans of the team yelled. Unsurprisingly, as it always seems to turn out, the move cost the Mets the lead and eventually the ballgame.

The decision to take a firing Syndergaard out of the game seemed puzzling at the time, and even prompted an apology to the team from Callaway. Previous gripes about his bullpen management include the overusing of relievers and misuse of the closer role. These perceptions of his bullpen management have brought Callaway under scrutiny, but is the heat warranted?

First it should be noted that managing a bullpen is not the only task a manager is asked to perform, and perhaps creating a good working relationship with the players and general manager is the most important goal for a manager. Regardless, we will look at some statistical methods of judging a manager’s bullpen management.

Setting up a comparison of a reliever’s xFIP and ggLI (Fangraph’s game leverage index) reveals how well a manager uses his better relievers in more important situations. Mets’ pitchers this year (minimum 10 IP) have a 22% correlation. Well-regarded bullpen manager Bruce Boche has a 56% correlation this year for comparison.

However, when looking at Callaway’s entire tenure that figure goes up to 43%, which is remarkably better than the correlation for the sum of all relievers over the same time period (25%). A pretty simple calculation, it still shows that Callaway has been able to effectively use relievers at an above average rate. There have been many occasions of him using the closer earlier in the ballgame when a high leverage situation presents itself. Instead, much of the criticism may stem from his overuse of productive bullpens arms.

Last week he used Edwin Diaz four out of five days and for the eighth time in 12 days, culminating in his second blown save of the season. Earlier in the year he drove a hot Seth Lugo into injury. It is more difficult to avoid these sorts of errors, and Callaway hasn’t figured it out yet.

But how much of a season is decided by bullpen management? One source shows reason to believe the range is only a one-win difference over the course of a season. WAR has never been kind to relievers either, and while relievers pitch in seemingly more important situations, at the end of the day starters still dominant a team’s pitching as a whole. This may change as teams play more and more “bullpen” games, but right now a starting pitcher has a much greater impact on the season. Callaway was brought in to help the Mets dazzling but underperforming staff, and it’s hard to argue that he hasn’t at least done that. Zack Wheeler’s improvement and Jacob deGrom’s Cy Young showcase his ability to coach starting pitchers.

Another point is that Callaway certainly has the locker room. While many fans in baseball see his apology after the game Tuesday as a sign of weakness, many of the players saw it as a message of strength and accountability.

This article has now stemmed a little from just bullpen use and Callaway’s managing as a whole, but this was needed to demonstrate that while in-game bullpen errors can be frustrating for a fan they still do not define a manager. Amid a sea of writing asking for his departure, this article defends the sophomore manager.