Big League Debut: Corbin Martin, Houston Astros

We’ve started doing something a bit different for our Big League Debut Posts for pitchers, and like Ralph Lifshitz did with Padres prospect Cal Quantrill and Angels arm Griffin Canning, I’m going to chart the debut for Astros righty Corbin Martin. The goal here is to watch the start, take notes and see how accurate the scouting reports are and really get a feel for how he attacks hitters. I cleared a spot on the corner of my sectional, pulled out the spreadsheet and turned out the lights in my living room on a rainy Illinois afternoon and watched Martin make his debut against the Texas Rangers.

Scouting Reports: The Astros selected Martin in the second round with the 56th pick in the 2017 draft, which was one of the picks that were transferred to the Astros as a result of former Cardinals Scouting Director Chris Correa logging into the Astros proprietary database. Martin was a standout two-way player in high school, but was a pitcher only while in College Station for the Aggies. He didn’t crack the Texas A&M rotation until his junior season and pitched more out of the bullpen for A&M due to his inability to harness his stuff. The Astros saw him at his best in the Cape and also what he was capable of on campus and he’s really put it together thus far.

Pitch Mix: For the pitch mix we will use the reports from our Astros top 30, written by Ralph, as well as
report at FanGraphs written by Eric and Kiley. Both reports cite his mid-90s heater and plus slider but when discussing the changeup both give the pitch an above average grade but Ralph writes, “…changeup that flashes above-average potential from time to time against lefties.” It’s a consensus above-average pitch, but Ralph seems to be questioning the pitch’s consistency. This is what I will watch for in this start. How he attacks hitters with the change.


Health: Martin has smooth, repeatable mechanics. It’s a low effort delivery with no glaring red flags. Martin has been healthy throughout his pro career thus far. The Astros utilize a piggy-back system for their arms throughout the minors, so that explains the 11 career relief appearances. Martin hasn’t exceeded 90 pitches in any of his appearances this season, and has only pitched into the sixth as a starter one time in his four starts. He hasn’t exceeded 99 pitches since entering the Astros organization.

Outcomes: FanGraphs describes Martin as a future number two or three starter, which is a huge player development win for the Astros. At 6’2”, 200 pounds he can handle a starter’s workload.


First Inning: For a kid from Houston who went to college at Texas A&M, making your debut on Mother’s Day with your mom in the stands has to get the juices going, and I think that’s what happened here as he hit 96 twice, 97 once and even 98 in this at-bat against Shin-Soo Choo. He also flashed his 83 mph breaking ball, which the Astros broadcast referred to as a knuckle curve, even though it looked like a slider. He ended the five-pitch at-bat against Choo with a 97 mph heater on the black to the lefty for his first strikeout of the day. Froze him looking.

The red-hot Danny Santana wasn’t going to wait around as he swung at the first pitch and grounded out. He then fell behind Elvis Andrus 2-0 but came with a 96 mph fastball, 84 mph breaking ball and then a beautifully placed 97 mph heater to put him down swinging.

11 pitches, seven strikes. Two strikeouts and one groundout thus far.

Second Inning: He had a clear plan to attack Mazara away and had a 1-1 count before getting him to pop up in foul territory to the catcher. He then dotted a fastball on the black to start his battle with Hunter Pence, and got him swinging on two breaking balls after that. Down on three pitches. Swinging and missing at both breaking balls which were again called knuckle curves by the broadcast. They also zoomed in on the pitch grip and it looked like a knuckle-curve grip but it has tremendous horizontal run, making me think slider. He then gave up a double to left center off the bat of left-handed hitting Asdrubal Cabrera on the breaking ball, but escaped the inning by getting Ronald Guzman to pop out on one pitch.

21 pitches, 14 strikes. Three strikeouts.

Third Inning: The third inning started with a long seven-pitch battle with Logan Forsythe that ended in a groundout. He also began throwing that changeup here, and the first one I saw was to Forsythe for a ball at 89 mph. Ninth hitter Isiah Kiner-Falefa came up next and Martin started the at-bat with a 97 mph heater for a ball. He tried to throw another one by the catcher, but it caught too much of the plate and Kiner-Falefa deposited into the Crawford Boxes for a solo homer. He fell behind Choo 3-0 after serving up the homer, but then painted a 94 mph fastball on the black for a strike, got him to foul off an 89 mph changeup with some fade and blew him away with a 97 mph fastball. Elite stuff here. Danny Santana came up and fell behind 0-2 and took two high fastballs at 96 and 97 before chasing a beautiful changeup off the plate for strike three.

42 pitches, 26 strikes. Five strikeouts.

Fourth Inning: The fourth inning was the most efficient frame for Martin, and he put the heart of the Rangers order, Elvis Andrus, Nomar Mazara and Hunter Pence down on eight pitches total, using all three pitches.

50 pitches, 34 strikes. Six strikeouts with eight swinging strikes.


Fifth Inning: Martin’s command got away from him a bit in the fifth, as he had a pair of three-ball counts but he still did not issue a walk. He features the changeup more against lefties, and Cabrera and Guzman saw four of them over eight pitches. He was down 2-1 in the count to Cabrera and got him to roll over a changeup for a groundout to first, and then he took Guzman down on four pitches. The changeup is a weapon against lefties. Logan Forsythe is amongst the league leaders in pitches seen per plate appearance, so it’s no surprise that he had two three ball counts against Martin. He attacked Forsythe with six fastballs in the 93-96 and ended up surrendering a double in the left centerfield gap, the third and final hit allowed for Martin. He froze Kiner-Falefa with a perfectly placed breaking ball on the outside corner with a 3-2 count to escape the jam. He did overthrow a changeup for a wild pitch in that at-bat, so that may be some of the inconsistency showing. That was the only blemish with that pitch all night though.

71 pitches, 49 strikes. Eight strikeouts and zero walks.

Sixth Inning: You had this feeling that the sixth would be his last inning no matter how it went due to his limited minor league workload, and after a walk and a strikeout they made the move and brought in Collin McHugh — the man he replaced in the rotation — to come in in relief. He fell behind Choo 3-0 after a pair of fastballs and a breaking ball missed the zone. He followed up with a fastball for a strike before losing Choo. He ended his day with a four-pitch strikeout on Danny Santana after falling behind 1-0. He swung and missed at a breaking ball out of the zone for strike three, and that is when A.J. Hinch pulled Martin to a loud ovation.

The final line: 5.1 IP, 3 H, 2 R, 2 ER, 1 BB, 9 K. 80 pitches, 49 strikes. 10 swinging strikes.


Conclusion: The scouting reports were spot on here. There was a little more velocity present, but it’s his big league debut in his hometown on Mother’s Day, which I think amped him up. There’s some concern here with him going deeper in starts, as the fastball went from 95-97 in the first four innings to essentially 94-96 to finish it out. Despite the lost tick, it’s still more than enough velocity in the tank to get it by hitters.

I’m in love with the changeup and the breaking ball. The breaking ball was better today but he worked the changeup in even against right-handers. He took control of both sides of the plate, which is something we haven’t seen recent call-ups do. I’m bullish on Martin going forward. If he sticks in the rotation he’s worth an add wherever you can grab him at. I’m a little concerned about his value in quality start formats, but the ratios will be strong. We should also see Josh James in the rotation at some point and the presence of Forrest Whitley complicates things a bit, but even if Martin gets sent down he’s done enough to ensure that the Astros keep giving him opportunities.