Peterson made huge developmental gains during his three years at Oregon and made headlines with a 20-strikeout performance as a junior in 2017. The Mets made him their first-round pick that June, taking the big southpaw with the No. 20 pick and signing him for slot value. Peterson made easy work of the Class A South Atlantic and Class A Advanced Florida State Leagues in his first full season and continued to pitch well in '19, spending the entire year at Double-A Binghamton before getting in extra work in the Arizona Fall League.
Peterson's fastball is average in terms of velocity, as he'll sit at 89-91 mph and touch 93, but few starters in the Minors can sink and command it as well as he does. He posted the third-best ground-ball rate (64.5%) among qualified Minor League pitchers in 2018, while his 52.6% rate at Binghamton was third-highest in the Eastern League (100 IP min.). Peterson traded some of those grounders for whiffs, as his strikeouts-per-nine rate jumped from 8.1 to 9.5 across his first two full seasons. He complements his sinker with a plus slider that has good depth and bite, registering in the 82-84 mph range. His fringy changeup registers in the same velocity band and would benefit from more separation.
Despite a lower arm slot from his 6-foot-6 frame, Peterson has demonstrated outstanding control of all his pitches while averaging 2.5 walks-per-nine across his first three seasons. Solid bat-missing ability and a knack for inducing weak, ground-ball contact points to more of a floor than ceiling for Peterson, but it might not take him that long to reach that potential.
Scouting grades: Fastball: 55 | Slider: 60 | Curveball: 45 | Changeup: 55 | Control: 60 | Overall: 50
Peterson honored his commitment to Oregon rather than sign with the Red Sox out of high school as a 28th-round pick in 2014. Three years later, after a huge step forward during his junior season that included a 20-strikeout performance, Peterson landed in the first round, going to the Mets with the No. 20 overall pick, and signed for full pick value. After having his pro debut shortened by an ingrown toe nail and then beginning his first full season behind schedule due to a minor knee injury, Peterson breezed through the South Atlantic League, posting a 1.82 ERA in nine starts at Class A Columbia before advancing to the Class A Advanced Florida State League.
Peterson's fastball is average in terms of velocity, as he'll sit at 89-91 mph and touch 93, but few starters in the Minors can sink and command it as well as he does. Logging 127 1/3 innings in his first full season, Peterson yielded only two home runs (0.14 HR/9) and posted the third-best ground-ball rate (64.5%) in the Minors among qualified pitchers. He combines his heater with an above-average slider that nets him whiffs as an out pitch, while his changeup, which flashes above-average, gives him a weapon against right-handed hitters. He fills out his four-pitch mix with a fringy curveball that he can throw for a strike.
Despite a lower arm slot from his 6-foot-6 frame, Peterson has demonstrated outstanding control of all his pitches, even if he can stand to refine his overall command some. Average bat-missing ability and a knack for inducing weak, ground-ball contact points to more of a floor than a ceiling for Peterson, but it might not take him that long to reach his potential as a No. 3 or 4 starter.
Scouting grades: Fastball: 60 | Slider: 55 | Curveball: 45 | Changeup: 55 | Control: 60 | Overall: 50
Peterson was a prospect coming from the Colorado high school powerhouse Regis Jesuit, but he opted to head to Oregon instead. Three years later, after a huge step forward during his junior season that included a 20-strikeout performance, Peterson landed in the first round and signed for full pick value with the Mets as the No. 20 overall pick. He made a brief pro debut in the short-season New York-Penn League.
Working with pitching coach Jason Dietrich at Oregon, Peterson struck out better than 12.5 per nine and walked just 1.35 per nine as a junior and brings a solid repertoire and that plus control to the pro game. From a velocity standpoint, Peterson's fastball is average, sitting in the low 90s and occasionally touching 95 mpg. But it plays up thanks to its plus sink and his ability to command it. He combines it with a slider that is plus at times and serves as an out pitch and has a changeup that flashes above-average that could be a good weapon against right-handers. He's mixed in a fringy curve for strike one at times in the past.
Despite a lower arm slot, Peterson has shown he has outstanding control of all his pitches, even if he can stand to refine his overall command some. He might be more floor than ceiling, but it might not take him that long to reach his potential as a No. 3 or 4 starter.
Scouting grades: Fastball: 60 | Slider: 55 | Curveball: 40 | Changeup: 50 | Control: 60 | Overall: 50
A raw and projectable prospect coming out of the Colorado high school ranks in 2014, Peterson developed into a more complete pitcher in three years at Oregon under the tutelage of pitching coach Jason Dietrich. A dominant junior season that included a 20-strikeout performance allowed him to rise up Draft boards, and he signed for full pick value at No. 20 overall.
Much of Peterson's success stems from his fastball-slider combination. He'll throw his fastball in the 89-94 mph range and backs it up with an above-average slider that flashes plus at times. He effectively mixes in an average changeup and will throw a below-average curveball as a "get me over for strike one" type offering. He can still refine his overall command, but his control has been tremendous, with a miniscule walk rate as a junior.
The 6-foot-6, 240-pound southpaw has a strong and durable build made for starting. The Mets hope the uptick he showed this spring continues as he embarks on his pro career.
Scouting Grades: Fastball: 65 | Curveball: 50 | Changeup: 40 | Control: 50 | Overall: 45
A one-time closer at College of Charleston, Peterson initially looked like a senior sign who could reach the big leagues quickly in the bullpen. Tommy John surgery in 2013 disrupted that plan, but he's returned and seems eager to make a beeline for Atlanta.
At 6-foot-5, Peterson has an excellent pitcher's frame. Now far removed from surgery, he's throwing his fastball consistently in the mid 90s. He throws it with a ton of sink to generate a ton of ground ball outs. He couples it with a power curve that should be at least Major League average, giving him a two-pitch combination good enough to work out of the bullpen at the higher levels. He's had a fringy changeup in the past, but doesn't need it much in short relief. He's generally around the strike zone.
Peterson isn't likely to close at the big league level, but his sinking fastball and breaking ball could be enough to allow him to compete in a Major League bullpen. Now 25 years old, it's time for the right-hander to get moving.
Scouting Grades (present/future): Fastball: 5/6 | Curveball: 5/6 | Changeup: 4/5 | Control: 5/5 | Overall: 5/5
The third time was the charm for Peterson, who was drafted out of high school by the Reds in 2008, as a College of Charleston junior in 2011, then signing as a senior with the Braves in 2012. He had moved from a starting role to the bullpen in his final season of college and that will be his future role. The right-hander pitched well for full-season Rome during his summer debut, moving into a closing role and even picking up a save during the postseason. With a good pitcher's frame, Peterson should have an above-average fastball and curve to work with in short relief. He even has a fringe-average changeup, though he may not need it out of the bullpen. He's the kind of senior sign who should move quickly through the system.