Collin McHugh is having a special season as a reliever for the Astros

Entering the 2018 season, the Astros had too many starting pitchers. They then converted one into a relief pitcher, and the results have simply been terrific.

Not counting spring training, Collin McHugh last started a game for the Astros on October 1st, 2017 against the Red Sox at Fenway Park. The game itself was the finale of the 2017 season, in which Houston emerged victorious to get to 101 wins. Very little was on the line as it had been already determined that the Astros and Red Sox would meet in the then-upcoming ALDS. Regardless though, McHugh was quite efficient in this start as he struck out eight hitters while allowing three earned runs over five hits in six innings.

Fast forward to 2018 and McHugh has not started a game for Houston during the regular season. This development doesn’t come to much surprise as the starting rotation is awfully crowded. The off-season acquisition of Gerrit Cole essentially forced McHugh out of the rotation. As spring training commenced, McHugh was the sixth-best starter on a staff that featured Justin Verlander, Cole, Dallas Keuchel, Charlie Morton, and Lance McCullers.

While a trade to a team in need of starting pitching was a possibility, the Astros decided to do something different: convert McHugh into a reliever. The results that followed have been something else.

Table 1. Collin McHugh statistics through August 16, 2018

IP              R     ER    ERA     FIP     BB%     K% 
55 1/3     9       7     1.14    2.51   6.3%    34.5%

Entering Friday, McHugh is one of eight qualified relievers to have a single-digit earned run total. Only Blake Treinen and Sean Doolittle have allowed fewer earned runs (6) than McHugh (7) for the 2018 season. He is also one of six relievers who currently have a single-digit run total (9). If the season ended today, McHugh would be the only qualified Astros’ reliever to have a single-digit run and earned run total for a single season. The age-31 right-hander is having a memorable season that may go down as one of the best from a reliever in franchise history. How was this guy not an All-Star?

Regardless of leverage, McHugh has been excellent in nearly all of his appearances. For example, he has held opposing hitters to a .105/.171/.263 slash line across 42 plate appearances in situations identified as high-leverage by Baseball-Reference. In medium-leverage situations, opposing hitters only have a .629 OPS against him while also holding offenses to a .436 OPS in low-leverage spots. The consistency across all leverage situations has felt like a breath of fresh air for a bullpen that has suffered various meltdowns this season.

As a byproduct of pitching in the bullpen, we’ve seen McHugh’s pitches show an increase in velocity in 2018. Nothing quite earth-shattering there as this is common for starters making the transition to relief. While his four-seam fastball won’t win any awards for velocity, an increase of nearly 2 MPH is beneficial. His curveball and cutter have also seen noticeable increases in velocity. We’ve seen the change in his slider’s horizontal movement along with the four-seam and cutter. There has also been tweaks to the vertical movement of his pitches. It is quite interesting to see the changes a pitcher makes when changing roles.

According to Pitch Info Pitch Types, McHugh has used five pitches this season, but has primarily utilized his four-seam, slider, and curveball. Without looking at video, I can’t help but wonder if the slider and cutter are the essentially the same pitch? Pitch classification, after all, isn’t infallible. Here is an interesting article from FanGraphs by David Laurila detailing the difference between the two pitches back in 2012. In his article, Laurila interviewed then-pitching coaches for the Braves, Roger McDowell, and Marlins, Randy St. Claire, who provided their opinions on the two pitches along with their differences. Even though the way baseball is analyzed has evolved in recent years, the information presented is still relevant today. I’d highly recommend that you’d read it for yourself.

Ask yourself about the state of the Astros’ bullpen if it wasn’t for McHugh? While I am sure it would still be a quality unit, the depth would be tested when you reflect on the various developments that have occurred this season. Like Hector Rondon, an off-season acquisition, McHugh has brought stability to a bullpen that has needed it. His transformation from a successful starting pitcher in the major leagues to a reliable reliever proves that value can be found in numerous places. If the ship stays on its current trajectory, we should be looking back on McHugh’s 2018 season as a fond memory.