Fredi, leverage, and bullpen management, Pt. 1

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Finally, I got to writing up this article. I’ve wanted for a long time to check out whether or not Fredi Gonzalez has been using his bullpen correctly. All season long, I’ve railed on the Marlins about pitching the right guys in the right innings and situations, so I checked out FanGraphs’ Leaderboards and got the team’s relievers’ leverage index (LI) data and FIP numbers for the seasons during which Gonzalez was the manager. I limited the sample to relievers who had logged at least 30 innings for the Marlins during the season.

In order to get some sort of ordinal value relative to the team’s average FIP, I took a sort of FIP+ approach, dividing the team’s average FIP by the FIP of the individual player. Using this format, we would expect a positive trend between leverage and FIP+; the higher the leverage index for a plate appearance, the higher the FIP+ we would expect, as a higher FIP+ would presumably mean a better pitcher. Here’s the graph, with the 2009 pitchers labeled first. On the x-axis is the average leverage index when the reliever enters the game (i.e. when the manager decides to have the reliever enter the game), while the

Immediately you can see that there’s something wrong with this picture. Leo Nunez, the team’s closer and reliever facing the highest leverages entering the game, is the worst reliever on the team in terms of FIP. Of course, FIP doesn’t take into account the fact that Nunez isn’t likely to give up as many home runs as he has, but even if you move him up to where Dan Meyer and Matt Lindstrom are, you’re still dealing with a reliever who is not performing the best on your team. There is no way Nunez should be averaging a starting LI almost 0.2 more than the next closest reliever.

If you looked at the track record of the team’s relievers in terms of defense-independent pitching, you would likely conclude that Kiko Calero was the team’s best bet in terms of a good reliever. Sure enough, Calero has been very good at missing bats and keeping the Marlins’ fairly poor defense out of the situation. However, Calero has only faced the third highest leverages when entering the game, despite having by far the best FIP, xFIP, and tRA on the team.

Baseball-Reference keeps track of the leverage of situations in which a reliever first enters. Calero leads the team in appearances in low leverage situations (leverage index less than or equal to 0.7) with 28, one more than the great Renyel Pinto. Meanwhile, Calero only has 18 high leverage appearances (leverage index 1.5 or higher), while Pinto has 24! For some reason, Fredi has cast Calero as a 7th inning guy while deciding that Nunez and Pinto are worthy of high leverage situations. And you wonder why Marlins fans want to pull their hair off with regards to the bullpen this season.

Tomorrow, I’ll talk about the last two years’ worth of Fredi’s bullpen management.