Harrison Musgrave was not a pitcher who began the season on the radar of too many PuRPs voters, given that he was an eighth-round pick in 2014 out of college and had gone through Tommy John surgery three years before getting drafted. After the draft, Musgrave threw 54 forgettable innings for rookie ball Grand Junction against hitters who were on average younger than him, which further threw voters off his scent. This year, though, the 23-year-old lefty starter began the season in High-A Modesto and from there his stock within the organization and with PuRPs voters has received some serious helium.
Musgrave proved to the Rockies that they made a good decision skipping him to High-A, throwing 90 ⅔ innings at that level with a 2.88 ERA, 8.2 K/9, 1.9 BB/9, and 1.10 WHIP to players who are around his age level. Musgrave then received a rare for the level mid-season promotion to Double-A New Britain. Those expecting to see Musgrave regress due to facing older (1.6 years on average) and more advanced Eastern League hitting were no doubt surprised (pleasantly so for Rockies fans) when he did not. For the Rock Cats, Musgrave posted very similar numbers: 56 ⅔ innings over 11 starts with a 3.18 ERA, 8.4 K/9, 2.1 BB/9, and 1.10 WHIP.
Wilson Karaman of Minor League Ball scouted some Modesto prospects back in May (well worth a read of the whole article) and had this to say about Musgrave:
The southpaw's delivery gives the appearance of some effort, mostly due to the speed with which he unleashes it. He uses a very low hand break, keeping the ball tucked off his back hip while he draws his right leg up abruptly. His leg kick is stiff to a rigid plant, and he really whips his arm through his release before a long deceleration through his front side, with a bit of a spin off to the third base side.
It's not a particularly fluid delivery, and there are some timing and balance concerns as a result which may limit his command development. He showed fringe to solid-average control of a four-pitch arsenal, including a fastball that sat 87-89 (t90), a slider in the 86-87 range, a low-80's change, and a curveball with decent depth in the high 70's. There isn't a plus offering of the bunch, though the curve showed as a potential 55 pitch. But he mixed his pitches well and showed a willingness to attack hitters to both sides of the plate. I'd peg him as a future 45 arm, with some upside to a number four starter if the command progresses.
I'd say that's a decent description of the pitcher Musgrave is right now -- someone with back of the rotation potential if he can continue to develop that command at higher levels. Musgrave didn't make my top 30 (just missed), but he had one of the best years among Colorado's minor league starters this season. Musgrave is a player who could easily provide value as an emergency starter in the next few years, though as with most prospects of his pedigree the odds are against him. He'll have a chance to make that prediction look silly (in a good way) as well, as I could see him starting either at Double-A Hartford or Triple-A Albuquerque. And if he pitches well there, he could be a rotation factor in 2017.