Last year, the Mets went into spring training under the assumption that four rotation spots were all sewn up. Jacob deGrom, Noah Syndergaard, Marcus Stroman, and Rick Porcello were going to make the rotation. The last spot would be a battle between Steven Matz and Michael Wacha, with a dark horse candidate in rising minor leaguer David Peterson.
It ended up playing out slightly differently, to put it extremely mildly. The start of the season was postponed due to the global pandemic, Syndergaard had to get Tommy John surgery, and as the season began to start up again, Marcus Stroman tore his left calf muscle and ended up opting out of the season due to concerns with COVID-19. Thus, the rotation turned into Jacob deGrom and a hodgepodge of everyone else. But one of the brighter spots was David Peterson, a homegrown Mets prospect who made his debut in the most difficult of circumstances and managed to impress.
Peterson went to high school in Aurora, Colorado, and was drafted by the Boston Red Sox in the 28th round of the 2014 MLB draft, but he didn’t sign, opting instead to go to the University of Oregon and play for their baseball team. In three great years in Oregon, he became the team’s number one starter, set the school record for strikeouts in a game with 17 in his junior year, and then broke his own record with 20 strikeouts a few weeks after that game. Then, in 2017, he was drafted by the Mets in the first round with the 20th overall pick.
Peterson was assigned to the Brooklyn Cyclones, where he spent the rest of the 2017 season but only appeared in three games. Peterson went into the 2018 season as the Mets’ second-best prospect in our rankings, and he started the year in Single-A Columbia, where he started nine games and totaled 59.1 innings pitched. He had a 1.82 ERA, 2.53 FIP, 8.65 K/9, 1.67 BB/9, and 0.15 HR/9.
Halfway through 2018, Peterson was promoted to High-A St. Lucie, and his numbers came closer to Earth. He had a 4.33 ERA, a much lower 2.98 FIP, 7.60 K/9, 2.49 BB/9, and 0.13 HR/9. His strikeout rate was down, and his walk rate was up.
In 2019, Peterson spent the entire season in Double-A Binghamton, starting 24 games and totaling 116.0 innings pitched. His numbers stayed largely around where they had been, with a 4.19 ERA, 3.19 FIP, 9.47 K/9, 2.87 BB/9, and 0.70 HR/9. His strikeouts were up, with 122 over those 116 innings. His walk and home run rates were slightly up, but he looked primed to make a debut for the Mets at some point during the 2020 season.
Once the 2020 season was delayed, Peterson’s chance to get a little time in Triple-A before making his major league debut disappeared. But when Syndergaard and Stroman then went down with injuries, Peterson found himself in the Mets’ rotation. During the shortened season, he he made ten appearances, nine of those being starts, and had a 3.44 ERA, 4.52 FIP, 7.25 K/9, 4.35 BB/9, and 0.91 HR/9, and he was worth 1.5 bWAR and 0.5 fWAR. He had a pretty good ERA all things considered, with his strikeout rate being down and his walk and home run rates being up, his walk rate considerably so.
At the major league level, it seems Peterson struggled to hit the strike zone at times, which would explain his higher walk rate and lower strikeout than he had in his minor league career. If he can hit the zone more often, he may be an even better version of himself, and since he’s also a ground ball pitcher, improved defense in the Mets’ infield should help him, too.
Projections for 2021 have Peterson improving slightly. Fangraphs’ ZiPS projection system projects a 4.14 ERA, 4.33 FIP, 7.95 K/9, 3.54 BB/9, and 1.07 HR/9. While his ERA and HR/9 are projected to go up, his K/9 and BB/9 are both expected to improve, getting closer to the numbers he showed throughout the minor league system.
This year, Peterson looks nearly certain to make the rotation out of spring training and to stay there for at least the first part of the season. Syndergaard isn’t expected to be back until midseason, and Carlos Carrasco recently suffered a hamstring injury. The Mets have have two rotation spots open at the start of the season behind Jacob deGrom, Marcus Stroman, and Taijuan Walker.
Peterson looks poised to show what he can do at the major league level again in 2021. With multiple spots open in the rotation for the time being, he’ll have plenty of chances to prove himself. Should he match or improve upon his 2020 performance, he could turn into a much-needed dependable rotation arm this season. And should he prove himself over the course of this full season, he would cement a spot in the Mets’ rotation moving forward.