Corbin Martin, Major Leaguer

Corbin Martin made his major league debut on Sunday, striking out nine and walking one over 5.1 innings, taking over, at least temporarily, the rotation spot of the struggling Collin McHugh. McHugh, a steady hand for the Astros since 2014, has seen his walk rate and home run rate increase, culminating in a three inning, eight earned run outing against the Royals on May 7.

Martin’s debut made him the fourth draftee from the 2017 class to reach the majors, after Kyle Wright, Nick Margevicius, and Griffin Canning. Long considered a talented prospect, Martin was heavily recruited out of Cypress Ranch High School and chose to turn down pro overtures to attend Texas A&M. The Houston-area native (he grew up in Hempstead and moved to Cypress for high school, both northwest of the city) had some ups and downs in his college career, often flashing tantalizing stuff but struggling to consistently harness it. He pitched nearly exclusively out of the bullpen for the Aggies during his first two years, amassing a total of just 44 innings pitched and striking out 54 while walking 33.

Scouts considered Martin’s 2016 summer campaign in the prestigious Cape Cod League to be a potential breakout. Pitching out of the bullpen for the Falmouth Commodores, Martin struck out 22 and walked just three in 15.2 innings, flashing a dynamic mid-90s fastball and an above average breaking ball to go along with his easy, athletic delivery. There was significant first round buzz heading into his junior season, and an expectation that he would cement himself atop of the Aggies’ strong pitching rotation and lead them through SEC play.

Martin ended up making 24 appearances and 13 starts as a junior for A&M, finishing third on the team in innings pitched behind Brigham Hill and Stephen Kolek. The inconsistent command he showed during his first two years in College Station was less significant but was still present, as he walked 38 batters in 87.2 innings. The intrigue scouts saw in Martin kept him in the conversation for those going toward the top of the draft despite the inconsistent performance. The Astros saw an opportunity to get the athletic right-hander in the second round of the 2017 draft, giving him a $1 million signing bonus with the 56th overall pick.

Martin was a better pro than college pitcher pretty much immediately after signing. He finished his debut 2017 season with a 33.6% strikeout rate and a 7% walk rate in 32.2 innings pitched in the GCL and the New York-Penn League. The Astros pushed him quickly through the system and started him in the Carolina League in 2018 when, after just 19 innings, he was promoted to Double-A. After five appearances (four starts) in Triple-A in 2019, Martin found himself on the mound in Minute Main Park less than two years after being drafted by his hometown team.

The ease with which he threw on Sunday was present as an amateur as well. As a junior in college he frequently worked his fastball in the mid-90s and would touch higher, and showed two impressive offspeed pitches. His breaking ball, the more consistently better of the two, was a power mid-80s downer with short, sharp tilt and swing-and-miss depth. His changeup, while used less than his breaking ball, had good fade and came out of the hand with good deception.

While his offspeed stuff helps round out his arsenal as a starter, his calling card throughout his professional career has been his fastball. Now consistently and comfortably in the mid-90s, Martin’s fastball averaged 95.7 mph during his big league debut and has been as high as 98.2 in the minor leagues. Martin’s 2,411 rpm average spin rate is fifth amongst MLB starters in 2019 with fastballs averaging above 95 mph thus far (not including “openers”), one spot behind last year’s National League Cy Young winner and two spots ahead of the American League Cy Young winner, albeit in far fewer innings. In Bauer Units, he ranks fourth among the same demographic, ahead of both.

In his minor league career prior to making his debut, Martin elicited a 14.4% swing and miss rate and a .258 wOBA against fastballs; in the major leagues in 2018, starters averaged a 8.9% swing and miss rate and a .355 wOBA against fastballs.

Martin’s arsenal – a mix of three pitches with above average characteristics – makes his ceiling quite high, that of a No. 2 starter. Whether he reaches that ceiling, of course, remains to be seen. The command issues that plagued him as an amateur has certainly improved in the pros, but his career minor league walk rate of 7.8% is far from elite. Eric Longenhagen and Kiley McDaniel named Martin the 50th best prospect in the game coming into this season, and ranked him third in the Astros’ system. As they mentioned in their write-up, Martin still doesn’t quite post the consistent bat-missing you’d expect of someone with his arsenal, and without some sequencing tweaks and continued refinement of his command, a reasonable expectation for his future in the big leagues would be more along the lines of a No. 4 starter with flashes of better.

The Astros’ history of developing and maximizing pitchers’ abilities is well-documented, and it will be interesting to see what A.J. Hinch’s staff is capable of with a pitcher like Martin, someone who has substantial ingredients on which to build. Watching his debut in his hometown on Mother’s Day was fun, and it sure was a feel good story. Watching his career unfold as he continues to learn to harness his arsenal will be fun as well.