Rotation plans for the Red Sox in the near term have come into focus recently, as manager Alex Cora told reporters (including MassLive’s Chris Cotillo) that right-hander Tanner Houck is likely to start the club’s game against the Orioles on Wednesday, though that could change if he’s needed out of the bullpen before then.
This doesn’t come as much of a surprise, as reports ahead of the activation of righty Brayan Bello from the 15-day IL last week indicated that the club could go with a six-man rotation at least through the off-day on this coming Thursday before transitioning to a five-man rotation that would likely leave Houck as the odd man out. Still, Cotillo goes on to note that the club does have other options: righty Nick Pivetta could be moved to the bullpen instead, or Bello, who was shelled for five runs in 2 2/3 innings of work in his first start coming off the IL, could be demoted to Triple-A.
Of the six members of the Red Sox rotation, Houck has actually been the best starter this season in terms of performance. In 21 innings of work, Houck has posted a solid 4.29 ERA, 11% better than league average by measure of ERA+, and a nearly matching 4.26 FIP. His strikeout (25.5%) and walk (9.3%) rates are largely in line with his career norms, as is his BABIP (.283). The most significant change from previous seasons for Houck in the early going this year is his groundball rate. Houck entered the season with a career groundball rate of 49.3%, but in his four starts this season, that figure has jumped all the way up to 58.9%, good for sixth in the majors among players with at least 20 IP.
While Houck’s start this season is encouraging, Cotillo notes that his success in a multi-inning relief role last year, when he posted a 2.70 ERA in 43 1/3 innings out of the bullpen, makes him a natural choice for the move. Meanwhile, Smith notes that Pivetta has resisted suggestions he could be ticketed for the bullpen after some early season struggles. Pivetta has yet to finish the sixth inning this season in a start and has posted a 4.58 ERA over 19 2/3 innings this season in spite of a deflated .275 BABIP that helps to explain his more worrisome 5.19 FIP.
Even in the event that Houck is ultimately sent to the bullpen, Boston brass will have to make another tough decision when lefty James Paxton returns from the IL, which he could do fairly soon. Paxton, Cotillo notes, has never appeared out of the bullpen in his career and struggled badly out of the bullpen in a rehab stint this season, allowing seven runs in less than an inning of work. With Paxton an unlikely bullpen candidate, the Red Sox are likely to once again be left to decide between a six-man rotation and bumping either Pivetta or Bello from the group when the veteran lefty is ready to be activated.