Paul Sewald may have entered last season as an afterthought, but he ended it one of the rare bright spots of the arduous 2017 campaign. A strong spring showing backed up his impressive minor league relief numbers (10.8 K/9 and 0.5 HR/9 over the previous five seasons), but a roster crunch combined with his lack of space on the 40-man roster dictated Sewald start the year in Las Vegas. As injuries, incompetence, and a domestic abuse suspension promptly ate away at the Mets’ 2017 bullpen, Sewald was called upon quickly, coming up for good in early May.
Sewald gradually progressed from bullpen depth to heavy rotation—for a time, Sewald and Jerry Blevins served as a de facto eighth inning righty-lefty setup tandem in the beleaguered Met pen. By the end of the season, Sewald had hurled more innings (65.1) than any Mets reliever in 2017 and appeared in more games (57) than any non-Blevins.
One could probably draw some disparate conclusions from Sewald’s 2017 peripherals—his 9.51 K/9 rate, 1.10 HR/9 rate, and quite low 65.0 LOB% could lead one to see a pitcher more likely to pitch to his 3.74 FIP than the 4.55 ERA he recorded in 2017. Whereas his rate of medium (50.0%) and hard (31.9%) contact allowed and his challenges retiring left-handed hitters (.281/.385/.441 against him) are a bit less promising.
At the 2017 trade deadline, the Mets brought in several relief prospects that may garner more interest as newer, more higher-end—and certainly higher velocity—pitchers than Sewald. However, Sewald’s solid rookie debut should leave him a favorite to earn a spot in the 2018 bullpen. At minimum, he projects as a serviceable innings-eater (PECOTA projects a 4.98 ERA over 51 innings, Steamer a 4.08 ERA over 45 innings).
Beyond the rare positive narrative of a 2017 Met exceeding expectations, though, there seems to be sufficient reason to hope Sewald can improve in 2018. A deeper projected bullpen front four of Jeurys Familia, A.J. Ramos, Anthony Swarzak, and Jerry Blevins should ideally expose Sewald to less high-leverage situations. With some judicious avoidance of tougher left-handed hitters, Sewald and his funky, three-quarters delivery could continue to be an asset—perhaps even a weapon—out of the 2018 Met bullpen.