Peterson is scheduled to start Sunday in the finale of the Mets' season-opening series with the Nationals, Anthony DiComo of MLB.com reports.
Peterson looked as though he would have to battle Joey Lucchesi for the fifth starter's role early in camp, but spots opened up for both pitchers after Carlos Carrasco suffered a hamstring tear that will sideline him into May. The lefty will now have at least the first month of the season to solidify a permanent spot in the rotation. The 3.44 ERA and 1.21 WHIP he submitted over his 10 outings as a rookie last season were strong on the surface, but most underlying numbers (7.8 K-BB%, 5.11 xFIP) painted a less rosy picture of his performance. He'll likely need to miss more bats or hope for continued good luck on balls in play in order to deliver another sub-4.00 ERA season in 2021.