NEWSLETTER
We’ve discussed the Cubs pitching staff with regular frequency here at Bleacher Nation over the past few weeks. While the starters have been generally solid, the bullpen has been far less consistent. Thought of as a strength coming into the season, we’ve generally accepted that the bullpen has been derailed by a few key injuries and some untimely performance, discussed earlier today. What we’ve failed to check in on, though, is how heavily the bullpen has actually been used, and to what end that is affecting their results.
Lucky for us, Craig Edwards did most of the heavy lifting, in a piece on The Current State of Bullpen Usage in 2015 at FanGraphs, with a hat tip to Baseball-Reference on some of the stats. Edwards’ article does a good job of checking in on how each bullpen is performing (via ERA and FIP), while digging into the individual bullpen usage statistics that should provide a little insight into the results. It’s a good read on bullpen usage overall, and a check-in on each team in baseball. It’s worth a read.
The three categories Edwards uses to measure bullpen usage are total bullpen innings, number of multiple-inning reliever appearances and reliever appearances on zero days’ rest. Given the underwhelming results so far, you may be surprised to learn where the Cubs fall, league-wide, in bullpen usage.
The Cubs’ bullpen ERA (4.38) is just 23rd in all of MLB, though their FIP (3.64) is 12th – and that kind of reversal is actually fairly uncommon, according to Edwards, because bullpens’ ERAs typically outpace their FIPs by over one-tenth. Might overuse, then, be the source of the Cubs’ bullpen woes? Well …
At just 98.2 IP, the Cubs’ bullpen falls into the bottom third 20th in overall bullpen usage for 2015. While we’ve discussed the idea that Cub pitchers are being pulled earlier than usual, it is not resulting in an overly taxed bullpen. The sole, or even primary, source of the Cubs’ frustration, this is not.
Anecdotally, pulling the starters early on a regular basis feels like it should result in the need for relievers to go multiple innings – Pedro Strop threw two against Milwaukee just the other night. But that, too, has not actually been the case for the Cubs. Through 32 games, the Cubs have asked a reliever to throw more than one inning fewer than twenty times – good for 24th in MLB.
The last statistic Edwards uses to identify bullpen usage is reliever appearances on zero days’ rest. Unlike the first two explanations, this one may have some traction with respect to the Cubs’ bullpen struggles. Through their first 32 games, Cubs relievers have had to pitch on zero days’ rest 24 times – sixth most in MLB. That is not the only reason for their struggles – the Cardinals’ successful bullpen tops the list – but it could provide a bit of insight. Perhaps the absence of Neil Ramirez and Justin Grimm combined with the unlucky sequencing of close games forced the Cubs to lean heavily on Strop, Rondon and Motte too many days in a row. Being used too many days in a row can mask over-usage, because the season total IP has the chance to remain normal.
Ultimately, and considering everything, over-usage doesn’t seem like it’s been the direct cause of the Cubs’ bullpen struggles in 2015. There’s a chance that some unlucky sequencing of tight games/high leverage situations has worked to their disadvantage, but it’s just as likely that they just haven’t been that good. Hopefully, among other things, the return of Grimm and emergence of Zac Rosscup will help spread out the load, and the bullpen can go back to being a strength.
