The Astros made it through a consecutive game gauntlet despite pitching injuries
The Astros’ pitching has been holding the team together, even when the offense doesn’t score a lot of runs. The remarkable part of this story is that the Astros have played through repeated pitching injuries. Spencer Arrighetti suffered a freak finger injury which will keep him on the IL for awhile. Both Hayden Wesneski and Ronel Blanco are on the IL with elbow injuries. Wesneski faces TJ surgery and Blanco is likely to face the same result.
So let’s look at where the Astros’ pitching ranks. For the season, the Astros’ ERA ranks 8th at 3.42, just behind the Rangers at 3.39. As the injuries crept up on the team, the Astros’ ERA over the last two weeks stayed fairly constant, even declining a bit to 3.38.
The expected (x) stats tell an even better story. The Astros are ranked 3d in x-BA (224), behind only the Yankees and Tigers. The Astros are ranked 5th in both x-SLG (.387) and xwOBA (.306). The x-stats give us some comfort that the Astros’ run prevention hasn’t been overly flukey.
But when you look at the last two weeks, it appears the starting pitching took the biggest hit—which squares with the fact that the injuries occurred in the rotation. In the past 14 days, the starting pitching is ranked 21st in ERA (4.01). But the bullpen stepped up to compensate for the rotation issues. Over the last two weeks, the Astros’ bullpen is ranked 4th with a 2.25 ERA and 5th in WHIP (1.06). On the season, the Astros’ bullpen is ranked 3d in WHIP and 2d in ERA. But the more recent period’s ERA and WHIP is slightly improved over the season results. According to Stuff+, over the recent two week span, the bullpen has been relying on extra good sinkers and sliders, with Stuff+ rankings of 2d and 4th in Stuff+ for sinkers and sliders, respectively. (Keep in mind that Josh Hader’s fastball is classified as a sinker, and sweepers are included in the slider category.
And we shouldn’t forget how important Josh Hader has been this season. Hader’s MLB ranking is 2d in both xwOBA (.232) and x-ERA (1.69). Hader also is ranked 4th in x-SLG, with an expected slugging percent of .255.
Okert, Sousa, and King join Hader as effective LHPs in the bullpen. They may not be quite as dominant as Hader, but they are nice surprises this season. All three have tremendous sliders, starting with Okert at a team-leading 126 Stuff+ on his slider. Sousa and King follow up with Stuff+ of 119 and 110 on their sliders.
Filling-in the Rotation
With the injury onslaught in the rotation, the Astros have filled in the open spots in a relatively serviceable manner. Rookies Ryan Gusto and Colton Gordon, as well as AAA call up Brandon Walter held things together somewhat. Gordon and Walter are similar lefties who rely upon command and lower velocity to get outs. Given the small sample size, the metrics are highly tentative. But x- stats and Stuff pitching model results may give us a little visibility as to how they pitched from a process standpoint.
Colton Gordon has an x-ERA of 3.02, which is in line with his FIP of 3.56. Walter has an x-ERA of 1.77 and a FIP of 1.68. Gusto has seen rougher times, with a 4.49 x-ERA, also in line with his 4.58 FIP.
If you are concerned about the potential quality of the opposing offenses in the small samples, the pitching model results are based on physical attributes of the pitches rather than the batter’s results. Thus, the stuff based models may alleviate the concern about the number of teams they have faced.
In terms of their stuff, Pitching Bot ERA estimates Gordon’s ERA at 2.95 and Walter’s at 3.51. Gusto’s PitchBot ERA is 3.95.
Pitching+ is a combination of Stuff+ and Location+. Walter has the highest Pitching+ ranking of the three pitchers with a 105. And Walter also has the highest Stuff+ at 109. Gordon has pitched to a 101 Pitching+ which is comprised of very good Location+ (111) and sub-par Stuff+ (95). Gordon basically has pitched to the description of his pitching style—command over stuff.
Gusto’s Stuff+ has been average (100) but his Pitching+ is below average (96) due to a weak Location+ (95). Although Gusto has a reputation of fairly good control his command has not always been great in the majors.
Stuff+ likes both the 4 seam FB and the sinker thrown by Gusto and Walter. Walter’s sinker was particularly good with Stuff+ of 134. Gordon’s slider is his only pitch that registers as quite good (Stuff+119). Gusto and Walter also threw good sliders (Stuff+ of 109 and 115, respectively). Again, keep in mind that sweepers are categorized as sliders.
I don’t know how long the Astros will continue pitching in the 6 man rotation. But that will affect the liklihood of continued appearances by the three fill-ins. However, all three pitchers, while not perfect, have been adequate so far. With the return of Spencer Arrighetti probably a month or more away, Gordon, Walter, and Gusto will have a useful function on this team in the near future.
It remains to be seen whether the the three rookies will continue to improve or whether the league finds and exploits their weaknesses. So it’s “TBD”—to be determined.