Many teams added to their rotations this offseason. Some opted to raise their ceiling by signing big-name free agents. The Blue Jays brought in Dylan Cease, the Red Sox signed Ranger Suarez, and the Tigers added Framber Valdez, to name a few. Others tried to maintain their floor by retaining existing starters and acquiring depth. The Padres fit the latter mold, as they brought in Griffin Canning, Germán Márquez, and Walker Buehler on low-cost deals this week.
While starting pitchers aren’t quite as volatile as relievers, injuries and underperformance still led many to post tough seasons in 2025. Tonight, we take a look at three bounce-back candidates: a top free agent, a veteran starter, and a minor-league signing.
Top Free Agent: Zac Gallen
Gallen has been a front-of-the-rotation arm at his best. From 2022-23, he posted a 3.04 ERA in 394 innings for the Diamondbacks. He struck out 26.4% of hitters in that span and ranked eighth among qualified starters with a 20.4% K-BB rate. His 9.3 fWAR ranked sixth ahead of Giants ace Logan Webb. Entering his age-28 season in 2024, there was reason to believe Gallen would continue to pitch at his prime level.
His numbers that year were still solid, if a step down from ace territory. Gallen missed a month with a right hamstring strain but still made 28 starts with a 3.65 ERA. He actually upped his groundball rate from 41.8% in 2023 to 46.2% in 2024. That said, his strikeout and walk rates both trended in the wrong direction, the latter now closer to average after two years of excellent control. Gallen slipped further in 2025. Though he stayed healthy and covered 192 innings in 33 starts, his ERA jumped to a career-high 4.83, his first below-average mark since 2021. The strikeouts slipped further to 21.5%, while his expected stats (4.28 xERA) suggest he was better than the surface numbers, but not by much.
Gallen entered the offseason as a buy-low candidate, as far as former aces go. We at MLBTR projected him for a four-year, $80MM contract even after his down year. In the end, his market didn’t develop as hoped. Gallen settled for a one-year, $22.025MM reunion with Arizona that nominally matched the value of the team’s qualifying offer in November.
Obviously, the team would love to see him return to his 2022-23 form. At the very least, Gallen figures to provide 30 starts of mid-rotation production, though he’ll undoubtedly aim for more in hopes of securing a multi-year contract next time around. The key for Gallen will be refining his breaking pitches, which graded out poorly in 2025 by Statcast’s run value metric. His curveball was worth 15 runs above average in 2024, but that fell to -4 this year, with opponents slugging over .200 more on the pitch. He’ll also look to bring up the strikeouts and keep the ball in the yard, having allowed the third-most home runs (31) of any qualified starter in 2025.
Veteran Starter: Sean Manaea
Manaea re-signed with the Mets on a three-year, $75MM deal during the 2024-25 offseason. At the time, he was coming off a strong 3.47 ERA in 181 2/3 innings in his return to full-time starting pitching (having mostly been a reliever for the Giants in 2023). With New York in 2024, Manaea struck hitters out at a 24.9% clip and did a decent job at keeping the ball in the yard compared to his career numbers. His .249 BABIP suggested he benefitted from good luck, but even so, he figured to provide solid, mid-rotation value on his new deal.
Unfortunately, his 2025 season was the exact opposite of his 2024. Manaea went down with a right oblique strain in March and missed the first three and a half months of the season. At one point, he experienced a setback when the team found loose bodies in his throwing elbow. Finally debuting on July 13, he made 15 appearances (12 starts) with a 5.64 ERA. Curiously, he posted that high ERA despite striking out a career-best 28.5% of hitters and walking a career-low 4.6%. Meanwhile, his expected stats (4.00 xERA and 3.30 xFIP) painted a much better picture than his surface-level numbers.
On the other hand, Manaea struggled badly with the long ball in 2025, allowing 13 in just 60 2/3 innings (1.93 HR/9). He also curiously ditched his sinker, which was worth 10 runs above average in 2024, to instead throw his four-seamer over 60% of the time. Opponents slugged .129 higher against the four-seamer compared to 2024, when he used it half as much. Manaea also upped his sweeper usage but saw diminished results, including a 9.6% drop in strikeout rate and a .148 increase in slugging.
Perhaps that was a mechanical problem. Manaea adopted a lower arm slot in 2024 and had a very productive second half. The combination of his oblique injury and further attempted mechanical adjustments may have contributed to his poor 2025 numbers, per Mets manager Carlos Mendoza (link via Alex Smith of SNY). The keys for him in 2026 will be regaining his pre-injury mechanics, differentiating the two fastballs like he did in 2024, and continuing to get chases on the sweeper.
Minor-League Signing: Walker Buehler
The current version of Buehler is far from the one who finished fourth in NL Cy Young voting in 2021. The now 31-year-old has pitched 266 1/3 innings since the end of that campaign. He missed all of 2023 while recovering from August 2022 Tommy John surgery. He returned for 16 starts in 2024, but the results were decidedly poor. Buehler struck out just 18.6% of hitters against an 8.1% walk rate and allowed nearly two home runs per nine innings. His once-vaunted four-seamer was now his least valuable pitch at 13 runs below average. Buehler pitched well in the postseason for the World Series-winning Dodgers, though. The Red Sox then took a chance on a one-year, $21.05MM deal.
Unfortunately, 2025 was not kind to him either. Buehler pitched 126 innings in 26 appearances (24 starts) with a 4.93 ERA. His velocity was down on every pitch except his slider. His strikeout rate fell to just 16.3%, while his 5.5% K-BB rate was fifth-worst among starters with at least 100 innings pitched. Boston released him at the end of August. Though he did alright in a small sample with the Phillies after that, it was clear that Buehler wouldn’t do nearly as well on the market this time around.
Now competing for a back-of-the-rotation spot in San Diego, Buehler will have to work hard to regain some value. He could start with adjusting his pitch mix. He has already steadily decreased his four-seam usage as it continues to lose velocity. Meanwhile, Buehler’s sinker was well-regarded by Statcast in 2025, grading out as 6 runs above average. Making the sinker his primary fastball might help him evolve into a soft-contact, groundball pitcher. His hard-hit percentage and average exit velocity were in the 70th percentile or better in 2025, so building on that might be his best path to prolonging his career.
Photo courtesy of Benny Sieu, Imagn Images
Zac Gallen top free agent. LOL
Me and @NashvilleJeff were just talking about Manaea in another post and how he did not get surgery to address the ‘loose bodies’ in his pitching elbow. He claims that he’s currently pain-free and that the issue essentially worked itself out. I didn’t see this mentioned above but it’s certainly something to think about this year, as far as him bouncing back is concerned.
Interesting notes about his sinker and four-seamer. Wonder if he will reverse course and start throwing the sinker more.
Manaea and Senga are the wild cards. If they get back to their best selves, that rotation is sick