Although the American League West over the last handful of seasons has been as tight a division as ever, it’s had a clear best team since the mid-2010s: the Houston Astros. They dominated the AL West and proved themselves time and time again as a juggernaut not just within the division, but within Major League Baseball as well.
Now, it’s the Seattle Mariners’ turn to reclaim the mantle heading into 2026, following a 2025 campaign that saw the M’s snatch the AL West crown from the Astros after Houston
had won four titles in a row and six in seven seasons (with the only outlier being the Oakland Athletics in the COVID-shortened 2020). The pressure will also be on them to finally snap their franchise-long drought of pennants, as they came closer than ever before in 2025 — topping the famous 1995 and 2001 teams — falling in an ALCS Game 7 heartbreaker to the Blue Jays.
2025 record: 90-72 (1st, AL West)
2026 FanGraphs projection: 88-74 (1st, AL West)
If there’s one team that is known for playing a specific brand of baseball across MLB, it’s the Mariners. While they are obviously more successful when they have the offense they did in 2025 — the ninth-ranked offense in all of baseball per fWAR and tied for the second-best in regard to wRC+ — their pitching comes first. Whether it’s the starting rotation or the bullpen, there’s something to love about the arms that have been assembled out in the northwest.
Beginning with the Mariners’ rotation, their top three pitchers are about as good as any in MLB. One might think it was Luis Castillo or Logan Gilbert who led the way statistically for Seattle, but it wasn’t. Instead, it was Bryan Woo, who pitched to a sub-3.00 ERA and a 3.33 xFIP, along with a staff and rotation-leading 3.6 fWAR. It was an entire fWAR point higher than both Castillo and Gilbert, who finished with 2.6, although Gilbert pitched upward of 50 innings fewer than the other two. And, of course, the fourth man in the rotation, George Kirby, can’t go unmentioned. He also finished with over 2.0 fWAR, and despite his 4.21 ERA, he probably deserved better according to the other metrics tracked, as his xERA of 3.88 and xFIP of 3.25 put him in a good spot to improve for 2026.
The name that made the biggest noise out of the bullpen was right-hander Andrés Muñoz, who finished with a 1.73 ERA and a 1.9 fWAR in 62.1 innings pitched. The 27-year-old has been about as consistent as anyone could ask for over the last three seasons, and the Mariners are going to look to him in high-leverage situations just as they did last year.
Obviously, though, the name that needs no introduction on the hitting side is catcher Cal Raleigh. He clubbed 60 home runs — a record for both catchers and switch-hitters — and tallied up 9.1 fWAR with a 161 wRC+ last season, competing with the Yankees’ Aaron Judge for the AL MVP award. Although he finished as the runner-up, Raleigh came away with his first All-Star appearance and a Silver Slugger, and is looking to dethrone Judge from the top of the American League food chain in 2026. The 29-year-old isn’t projected to have nearly the kind of season he had in 2025, but he is still projected to be a top player in the AL, with FanGraphs suggesting that he will hit somewhere around the 40 home run mark with a 130 wRC+ and 6.4 fWAR.
Along with Raleigh, the Mariners over the last couple of seasons have accrued plenty of talent to keep their bid for a World Series about as strong as possible. There’s Julio Rodríguez, Randy Arozarena, J.P. Crawford, and Josh Naylor, whom the Mariners secured on a five-year deal worth $92.5 million this offseason after bringing him in last year, along with 21-year-old secon dbaseman Cole Young, who was called up last season and played 77 games. There’s also the versatile Brendan Donovan, new from the Cardinals as a trade addition, and long-ago Yankees farmhand Rob Refsnyder, who turned himself into dangerous platoon bat for the Red Sox and joined the M’s in free agency.
All these names are now on a team that was on the brink of its first Fall Classic in 2025. Now, they’ll look to make it even further and vie for a championship in 2026.
More Pinstripe Alley MLB team season previews can be found here.
