Analyzing the Reds’ bullpen struggles

The Reds’ bullpen has been a clear weak link in the early goings this year. Going into Friday’s game, the Reds bullpen ranks 29th in the league with a 6.00 ERA in 72 innings. While the advanced metrics are a bit more optimistic, they still rank near the bottom of the league. Their 5.51 FIP ranks 29th, while their 4.83 xFIP ranks 27th and their 4.30 SIERA ranks 28th. All other stats referenced in this article are through Thursday, April 22.

Digging deeper on the staff as a whole, their strikeout rate ranks around league average at 25.3%, though their 10.25 K/9 ranks 9th in the league. This is in part due to the frequency with which the staff is walking batters, ranking second worst in the league with a 14.2% walk rate.

The long ball has also been an issue, with their home run rate ranking as the third worst in the league. A potential positive sign is that their current HR/FB rate is 18.2%, second worst in the league. This is a metric that typically stabilizes over a larger sample size and can be fluky in smaller samples, and the current number feels unsustainably high.

Looking into the individual pitchers on the staff, we can immediately identify the strengths and weaknesses. Four pitchers ranked better than average in strikeout rate: Tejay Antone, José De León, Lucas Sims, and Sean Doolittle. Note that De León’s stats below are only as a reliever. Notably, only one pitcher has ranked better than average in walk rate: Sal Romano.

Image: Fangraphs

Another stat featured above is CSW% (called strikes + whiff percentage), which is the percentage of pitches that are either a called strike or a swing and miss. Five of the Reds’ relievers have a CSW% better than the league average of 28.3%.

The below chart shows Reds relievers ranked by SIERA (skill-interactive ERA). What generally makes SIERA more accurate than FIP and xFIP is that it factors in contact quality, adjusting for a pitcher’s tendencies to allow ground balls, fly balls, and pop outs. For a more in-depth explanation on SIERA, check out this article from Fangraphs. Notably, the league average SIERA for relievers this year is 3.78.

Image: Fangraphs

As you might expect, the same four pitchers were near or better than league average. Again, note that De León’s stats above are only as a reliever, though his combined SIERA including starts is an even better 2.80. Fulmer’s SIERA is also respectable, though still worse than league average.

Four Reds stand out as having a particularly poor SIERA: Sal Romano, Cam Bedrosian, Cionel Pérez, and Amir Garrett. Of those four, Bedrosian has already been designated for assignment and subsequently elected free agency, and Pérez was optioned prior to Friday’s game.

You can also see how other ERA estimators like xFIP and xERA compare above. Notably, xFIP is not as optimistic about Sims or Doolittle, while xERA is also very pessimistic about Doolittle. Meanwhile, xERA is much more optimistic about Pérez. While De León does not have an xERA listed on Fangraphs as a reliever, his overall xERA this year is 4.30.

With Garrett, given his track record, it’s likely he will be able to turn his numbers around and it’s probably too early to be overly concerned. Romano doesn’t have the same track record, so it’s likely his leash is a lot shorter and a change could be made if he continues to struggle.

The key for the Reds’ bullpen seems to be those last few depth spots. The Reds have two truly elite relievers in Sims and Antone, and two other very solid arms in De León and Doolittle to join them. The key will be turning around Garrett’s season and finding a few other arms to provide quality innings for the team. If they can do that, the Reds’ bullpen could go from the disastrous results they have received thus far to a very solid group.

Featured Image: https://twitter.com/Reds/status/1292506272185692160?s=20

Kyle Berger

Kyle Berger is a lifelong Reds fan who has lived in the Cincinnati area for his entire life. Kyle has always been interested in the analytics side of baseball, and recently graduated from Miami University with a degree in Business Analytics. You can follow him on Twitter @KB_48, where most of his Tweets are about the Reds or baseball in general.

2 Responses

  1. kmartin says:

    Good article, but when I think of “truly elite relievers” I think of guys like Craig Kimbrel, Aroldis Chapman, Josh Hader, or Kenley Jansen. I certainly hope Sims and Antone become truly elite relievers but I think we need a few more years of data.

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