The AL West is up for grabs in 2025. After a disappointing 2024 season where just the division-leading Astros made the playoffs, many other teams are looking to take the next step forward and compete for the division title in 2025.
Outside of the Mariners, who had one of the most dominant starting rotations in baseball, or the division-leading Astros, pitching was fairly weak in the AL West. The reigning World Series champ Rangers were hampered by injuries, while the Angels and Athletics simply didn’t have enough pitching talent to compete.
Regardless, many pitchers either underperformed or didn’t live up to expectations in 2024. Some of these pitchers were Tyler Mahle, Hayden Wesneski, and Reid Detmers, who all had varying mixes of injury, lack of opportunity, or poor performance in the 2024 MLB season. While these pitchers may have had down seasons, they all are in good positions to bounce back and reemerge as solid starters in 2025.
Tyler Mahle
Tyler Mahle had a second consecutive incomplete season in 2024, making just three starts after making four in 2023. Even after losing his 2023 season to Tommy John surgery, Mahle signed a 2-year, $22 million deal with the Rangers before the 2024 season with a projected return around the All-Star break. Once returning, Mahle made three starts before his season ended preemptively with a shoulder injury.
Still just 30 years old, Mahle has a chance to get back on the mound and make an immediate impact for a Rangers team needing all the pitching it can get. After a World Series title in 2023, the Rangers pitching staff collectively had a 4.35 ERA in 2024, sandwiched between the lowly Oakland Athletics and Washington Nationals in team ERA.
Now healthy, Mahle could be a key for the Rangers to win the AL West in 2025. Still, there are some signs to observe in Spring Training and beyond to ensure Mahle has what it takes to post strong numbers after losing two years to injury.
Mahle’s four-seam has always been his strongest pitch, running an elite 32.9 CSW% in 2022 due to its elite shape and -4.2 VAA boosting its performance up in the zone. While his fastball graded out fine in a limited 2024 sample, its velocity was down from 93.2 to 91.4, and Mahle’s VAA was closer to league average at -4.5. Mahle’s splitter was also less effective than in 2022 (69 Stuff+ in 2022, down from 84), losing some vertical drop and thus grading out worse.
This was likely due to his nagging shoulder injury, which led to him missing his final few starts. As mentioned earlier, Mahle is healthy entering 2025, and the Rangers are expecting a lot. A strong Spring Training would be a good sign for Mahle’s effectiveness, although a healthy season should be priority #1 for the Rangers.
Mahle’s 2022 season saw 23 starts with two teams, posting a 4.40 ERA/3.87 FIP over 120.2 innings. I would consider a season comparable to these numbers in 2025 a success, although Mahle has shown he is capable of even better in the past.
Hayden Wesneski
Hayden Wesneski had a solid 2024 season, posting a 3.86 ERA/4.51 FIP in 28 appearances as a starter and reliever. Traded to the Astros in the Kyle Tucker deal, Wesneski’s future as a starter has yet another chance to prove itself in a heavily injured Houston rotation.
Wesneski was featured in my version of this article last year, and while his 2024 season was far from disappointing, I expected more. Making just seven starts in the Majors, Wesneski was relegated to a long relief role most of the season when he wasn’t in AAA, where he made seven appearances and three starts. Wesneski also missed about two months due to a forearm injury, making a few relief appearances in late September upon returning.
Now in Houston, Wesneski is projected to open the 2025 season in the Astros’ rotation, which is missing starters Cristian Javier, Luis García Jr., and J.P. France to major arm injuries. A big season for Wesneski could make the Astros all the more intimidating, and he has all the tools necessary to do so.
Even though his ERA/FIP improved from 2023, I consider a real bounce-back for Wesneski mirroring his small 2022 season over a larger sample—this would be mid-3s FIP and ERA ideally. This could’ve happened in 2024, although his 4.52 FIP was far too inflated, likely due to his 1.60 HR/9.
A lot of Wesneski’s underlying stats would indicate a FIP improvement—a 16.9 HR/FB% is far higher than league average, and his elite 30.3 CSW% in 2024 should leverage more strikeouts than it did in 2024 (23.7 K%, roughly league average). Wesneski also walked fewer batters than in 2023 and induced a great mix of soft contact (87.6 average EV) and ground balls (44.0 GB%), which should help the home runs come down over a larger sample.
Wesneski significantly changed his mechanics in 2024 as well, adding two inches of extension (now 7′) and raising his arm angle 11 degrees. By doing this, Wesneski induced more ground balls, avoided more barrels, and gathered more called strikes and whiffs than ever (30.3 CSW%, previous best was 28.7% in 2022).
Now, I believe Wesneski has what it takes to take the next step forward. As the Astros’ starting pitching gets healthier, Wesneski could be moved to the bullpen, although I wouldn’t expect it for long. The Astros’ strong coaching staff could be just what Wesneski needed for that next step, and I would expect it in 2025.
Reid Detmers
Reid Detmers had a disaster of a season in 2024. Bouncing between AAA and MLB, Detmers posted a 6.70 ERA/4.72 FIP in the Majors over 17 starts. Detmers’ numbers in AAA weren’t much better, and while Detmers was frequently considered a trade candidate throughout the season, nobody was willing to take the risk entering 2025.
Now entering his fourth season in MLB, Detmers needs to take a step in the right direction. Still just 25, Detmers was an aggressive call-up for the Angels (shocking, right?) at just 21 and struggled, but quickly found his footing the year after, posting a 3.77 ERA in 25 starts in 2022. After a decent 2023 season, Detmers was lost in 2024, despite his stuff grading out better than ever.
Sure, Detmers got unlucky in a lot of ways. A 17.1 HR/FB%, 3.86 xFIP, and 62.9 LOB% indicate positive regression is due. A 27.9 K%, 30.9 CSW%, and 40.1 GB% were all career highs as well. With all these stats that went right, Detmers has the bones of a good pitcher.
So what went wrong? Simply put, just about everything else. While Detmers’ stuff was sharp, his sequencing and command were poor, leading hitters to jump on just about anything he threw in-zone.
As home runs were generally Detmers’ biggest problem, most of his approach was heavily susceptible to them. Detmers threw inside and high far too often, with hitters frequently pulling fly balls (47.9 Pull%, 43.8 FB%)—as pulled fly balls are ideal for hitters, they turned into lots of home runs.
When Detmers got into two-strike counts, he ran a phenomenal 22.3% putaway rate, which was easily a career best. Detmers got some chases too (31.4 O-Sw%, career best), but Detmers could not pitch in the zone without running into damage.
There are still some good signs with Detmers, as his swing-and-miss numbers grade out well and he got more ground balls than ever in 2024. Still, something needs to change. Some command improvements or an approach fix are ideal, but how Detmers would go about that is where it gets tricky.
Regardless, Detmers is confident he can bounce back in 2025, which is most important. Detmers is just 25 and has shown promise in the past, so a healthy offseason could have been just what Detmers needed to have a fresh start in 2025 and bolster a solid Angels rotation.
