Astros Observations: Hector Rondon, unsung hero of the bullpen

A former closer from the Chicago Cubs may help determine if the Astros need to acquire additional bullpen help this summer.

Today’s post will be about Hector Rondon and how his performance has been a much-needed shot in the arm for this Astros‘ bullpen. But I would like to provide the overall context of Houston’s relief corps before singling out the former Cubs’ closer .

Statistically speaking, the Astros’ bullpen is one of the best in baseball. In 169 innings, Houston’s relief corps have posted the fourth-lowest ERA (3.09), lowest FIP (2.93), and fifth-highest fWAR (2.6). This unit also has the third-highest strikeout rate (28.6%) and the lowest walk rate (6.5%).

Despite the Astros’ bullpen being statistically great, there have been issues in high-leverage situations.

This lack of successful consistency in high-leverage is quite evident in the later innings with a small lead and particularly one five-run lead in Cleveland. FanGraphs has a metric called Clutch, which “measures how well a player performed in high leverage situations.” The Clutch metric gauges, per FanGraphs’ David Appelman, “how much better or worse a player does in high leverage situations than he would have done in a context neutral environment.”

Currently, the Astros’ bullpen have the worst Clutch rating in baseball at -2.70. The team also has eight blown saves on the season. And a 4-12 record in one-run games. Makes sense if you have watched a lot of the Astros this year. Now, before you start worrying about saves, there are 14 teams with more blown saves than Houston. Blown saves are not good, but are often an over-used and inefficient litmus test on bullpen performance. By the way, the vaunted Yankees’ bullpen has eight blown saves, the same number as the Astros.

Now, Rondon was signed last offseason to provide more stability to the bullpen. As you may recall, the Astros were scrambling by the time of the postseason to find suitable relievers for the later innings. Thank goodness for Charlie Morton and Lance McCullers.

The former Cubs’ closer was coming off a disappointing 2017 campaign when the Astros signed him. In 57.1 innings last season, Rondon posted a 4.24 ERA and 4.12 FIP to go with an 8.4% walk rate. Overall, Rondon’s 2017 season was the worst season of his career since his 2013 rookie campaign. But there were encouraging signs of a possible turnaround as his strikeout remained near 29% and his velocity remained near his career averages.

Fast forward to June 7th, and the Astros have to be pleased by the results from Rondon.

Rondon has thrown 22 innings for this season and he has posted a 1.64 ERA and 1.89 FIP. There also has been a noticeable increase in velocity as his fastball is now averaging 97.5 MPH, which is roughly 1 MPH higher than the past two seasons. In fact, all of his pitches have experienced an increase in velocity. Then there is the pitch usage.

Yes, the Astros have Rondon throwing fewer fastballs and sinkers by a combined 8.3% in lieu for more changeups and sliders.

Thanks to Baseball Savant, we can see how effective Rondon’s pitches were, or weren’t, based on the wOBA allowed to opposing hitters. For example, Rondon allowed a .366 wOBA last season on any pitch listed as a fastball, which includes sinkers. Thus far in 2018, he has allowed only a .253 wOBA on the exact same pitches. Now, the opposite occurs for his offspeed pitches as his wOBA has increased from .227 in 2017 to .275 in 2018. The increase of usage of his offspeed offerings could explain the increase. At the same time, a .275 wOBA is still good as an average wOBA per FanGraphs is .320.

Next: Astros Series Preview: Deep into Texas enemy territory

The Astros’ front office and coaching staff have Rondon essentially throw more the pitches that were successful. A more balanced pitching attack, if you will. Hitters have not been able to fully adjust quite yet. That said, Rondon himself has a -0.62 Clutch rating. Only time will tell if the former Cub experiences more high-leverage situations for the Astros. But if he continues to pitch like he has this season, specifically last night against the Mariners, then the Astros may be forced to give Rondon another chance at finishing games more often. If he succeeds, then Houston’s front office may not feel the need to pay a dear price for more relief help this summer.

**Statistics and information courtesy of Baseball Reference, Baseball Savant, and FanGraphs**