Martín Pérez Dons the Red Sox Again by Jay Jaffe January 19, 2021 The Red Sox didn’t have much to write home about in 2020, skidding to a 24–36 record and a fifth-place finish in the AL East. Though they have yet to make a major splash thus far this winter, they did make a move on Saturday, re-signing southpaw Martín Pérez to a one-year deal that constitutes a pay cut and opens questions about a rotation that was the majors’ worst in 2020. Pérez, who turns 30 on April 4, joined the Red Sox after an uneven 2019 spent with the Twins, during which he was very good in the first half and nearly useless in the second. He was the only Boston pitcher to make more than nine starts last season, and, well, the results weren’t stellar, as he once again faded late in the year. He did start 12 times, tied for fifth in the majors, and his 4.50 ERA in 62 innings was actually a bit better than league average (97 ERA-) despite a 5.58 ERA over his final six starts. His 4.88 FIP, though, was a significant step down from league average (111 FIP-); his 17.6% strikeout rate was only a bit off his career-high 18.6% in 2019, but his 10.7% walk rate was a career worst. All told, his season was worth 0.4 WAR, which prorates to about 1.0 over a full campaign. Pérez had been worth more in five of his previous seven seasons in Texas and Minnesota, so there’s no mistaking this for being the top of his game. What was interesting about Pérez’s performance — and I admit I may be stretching the definition of “interesting” — was that he posted the lowest groundball rate of his career. His 38.5% rate was 12 points below his previous career mark and 9.5 below his 2019 mark; eyeballing our season stat grid, I found only half a dozen bigger drops over the past decade, though 62 innings doesn’t tell us as much as a full-season workload. Anyway, Fenway Park isn’t a great place to start serving up fly balls, but Pérez’s 1.16 homers per nine was his lowest mark since 2017, and he had no real difference between home and road splits, which may tell you a bit about the East Coast ballparks in which he toiled. Since Pérez is going back to Fenway, the fly balls do rate as a concern, but his Statcast numbers do show that he’s done a good job of limiting hard contact since ditching his slider in favor of his cutter in 2019. In 2020, his 29.2% hard-hit rate ranked in the majors’ 90th percentile, and his average exit velocity of 86.3 mph was in the 85th percentile, versus 96th for the former and 93rd for the latter the year before. Before that, he’d never been better than middling in either category, and sometimes bad enough to slip into the bottom quartile. Pérez threw the cutter 30.8% of the time in 2019 and 32% in ’20, and he’s gotten good results with the pitch. When batters have made contact with his cutter in that span, they’ve produced the majors’ second-lowest exit velocity and xwOBA: Batted Ball Results on Cut Fastballs, 2019-20 Rk Pitcher Team CT BBE Tot BBE % CT xwOBA EV 1 Ryan Yarbrough Rays 240 587 40.9 .353 82.9 2 Martín Pérez Twin/Red Sox 204 717 28.5 .307 84.8 3 Dallas Keuchel Braves/White Sox 125 546 22.9 .372 85.1 4 Lance Lynn Rangers 140 786 17.8 .309 86.0 5 Marcus Stroman Blue Jays 127 555 22.9 .382 86.1 6 Aníbal Sánchez Nationals 183 697 26.3 .328 86.3 7 Eric Lauer Padres/Brewers 132 495 26.7 .365 86.4 8 Aaron Civale Indians 113 388 29.1 .371 86.7 9 Walker Buehler Dodgers 104 571 18.2 .340 86.8 10T Kenley Jansen Dodgers 151 220 68.6 .357 86.9 Adam Wainwright Cardinals 169 711 23.8 .377 86.9 12T Josh Tomlin Braves 201 380 52.9 .338 86.9 Trevor Bauer Indians/Res 106 715 14.8 .302 86.9 SOURCE: Baseball Savant Minimum 100 batted ball events via cut fastballs. % CT = percent of batted ball events via cut fastballs. While Pérez got fewer grounders via the cutter in 2020 (34%) than 2019 (44%), that alone doesn’t compensate for his shifting profile. He also dialed back his sinker usage from 24.8% to 17.7% and compensated with his curve and changeup. That cost him some grounders, and he also got fewer grounders this past year via his four-seam fastball — a drop from 40% to 19% — while doing a much better job of keeping those pitches out of the center of the strike zone: Thanks to the better location, batters went from hitting .370 and slugging .740 when they connected with Pérez’s four-seamer in 2019 to .233 and .533 in ’20, respectively — and he did that despite the average velocity on that pitch dropping from 94.2 mph to 92.2. Still, it was an unremarkable season all told for Pérez, and effectively, he’s taking a small pay cut after making $6 million in 2020 and then accepting a $500,000 buyout after having his $6.85 million club option declined. He’ll get a $4.5 million base salary for 2021, with additional boosts of $100,000 for passing the 130-, 140-, 150-, 160-, and 170-inning thresholds. Those same thresholds also add $100,000 apiece to his $6 million club option for 2021, while reaching 180 innings adds another $250,000, meaning that he could max out with a $6.75 million option. While Pérez is a solid choice to provide stability at the back of a rotation, the real question is how much closer to the front of the Red Sox rotation he’ll be in 2021. Between the departure of Rick Porcello via free agency, the inclusion of David Price in the Mookie Betts trade, and the subsequent losses of Chris Sale to Tommy John surgery and Eduardo Rodriguez to COVID-19-related myocarditis, the Sox had just one rotation holdover from 2019 to ’20: Nathan Eovaldi, who was limited to nine starts by a right calf strain. As a result, the team was forced to call upon the likes of rookies Tanner Houck and Chris Mazza, veterans Colten Brewer, Zack Godley, Nick Pivetta, and Ryan Weber, and assorted openers to round out their starting five. The results were dismal: The unit’s 5.34 ERA ranked 25th in the majors; its 5.50 ERA 29th; and its 0.4 WAR dead last. The plan is to have Eovaldi — who hasn’t made more than 21 starts in a season since 2015 — and Rodriguez in the rotation to start 2021. Sale, who went under the knife last March, will hopefully be back by midseason, as the team is taking a conservative approach with his rehab. The Sox are still in the market for a mid-rotation upgrade, with the Boston Globe’s Alex Speier listing names such as Rich Hill, Jake Odorizzi, James Paxton, José Quintana, and Masahiro Tanaka among the potential targets. Unless they land one of them, then Houck, Pivetta, and the recently signed Matt Andriese will be in the mix to fill the other two spots at the start of the season. Prospects Bryan Mata and Connor Seabold, who have 18 starts between them at Double-A and nothing higher than that yet, could be in play for later in the year. Most of those pitchers may be better fits in the bullpen than the rotation, but if the Red Sox aren’t pushing to compete, now is the time to find out what they’ve got. Meanwhile, chief baseball officer Chaim Bloom is reportedly considering the possibility of a six-man rotation given the increased workloads his starters will face. Besides Sale and Rodriguez, none of the other pitchers currently on the roster threw more than 135 innings in 2019. All of which is to say that amid so many question marks, Pérez brings the Red Sox a bit of certainty if not a great deal of upside. He’ll eat innings in what isn’t likely to be the most memorable Red Sox season of the millennium. If he’s good enough, he might pitch himself onto a contending club down the stretch.