The 2025 campaign was a rollercoaster for the Mariners. Seattle won 90 games and the AL West title for the first time in over 20 years, and nearly made it to the World Series for the first time in 2026. But the 2026 season was very different for the Mariners. The club won just 76 games, had problems scoring runs, and ultimately ended the year by removing Dan Wilson as club manager.
The Offense
| Stat | Number | Rank |
|---|---|---|
| Runs Scored | 664 | 28th |
| Home Runs | 182 | t-16th |
| OPS | .693 | 27th |
| Whiff% | 26.1 | 22nd |
| Hard Hit% | 38.3 | 19th |
The Pitching
| Stat | Number | Rank |
|---|---|---|
| Starters’ ERA | 4.05 | 10th |
| Relievers’ ERA | 4.46 | 22nd |
| Strikeouts | 1392 | 12th |
| Whiff% | 25.1 | 15th |
| Chase% | 32.2 | 5th |
The Good
Yet again, the Mariners were able to roll out an impressive pitching staff.
The homegrown pitching staff was excellent. Logan Gilbert struck out 205 batters and missed more bats than any other starter in the Seattle rotation.
Some of Bryan Woo‘s peripherals might not have been great, as he posted an ERA north of 4.00 after a dominant 2025 campaign. Still, the right-hander struck out 175 over 172 IP and ranked 21st in opponents’ wOBA (.285).
Emerson Hancock, a former first-round pick from 2020, finally had that big year. Hancock, who shook up how he attacked hitters, posted a tidy 3.57 ERA and struck out 126 over 138.2 IP for the M’s in 2026.
Bryce Miller and George Kirby both had their moments but the two combined to make 51 starts this past season. Miller had a great start to 2026 before opposing hitters got to him more as the year went on. He allowed 14 home runs and had a 5.55 ERA in his final 14 starts. Kirby (5.09 ERA) also had a tough second half.
Still, the two had two of the best fastballs in MLB, at least when it came to expanding out of the zone. Kirby and Miller ranked second and third, respectively, in Four-Seam Fastball Chase% in 2026. Will Dion (Nationals) and Drew Rasmussen (Rays) were ahead and behind them, respectively.
Kade Anderson torched Double-A hitters in 2026. His reward for that? Nine MLB starts at the end of the year, in which he struck out 32 over 35 innings and looks like a keeper. The metrics back that up.
Moving to the offense, Randy Arozarena had a fantastic season in what could have been his last season as a Mariner.
Arozarena hit a team-high 26 home runs for the Mariners, in a year where he had to do it all. Get on base, drive runs, and move things alone on the basepaths. The veteran outfielder and now-free agent had himself another 20-stolen-base campaign, with 26 this past year.
Unlike in 2025, Arozarena was the only Mariner to have at least 25 home runs this season. We’ll get more into that in the next section. But Seattle did have four 20+ home run hitters, with Dominic Canzone and Julio Rodriguez in that group.
Canzone broke through as a regular in 2026. His 23 home runs were tied for second on the team, and the 55 extra-base hits Canzone accrued were good for second, behind only Arozarena.
Cole Young hit 17 home runs and 40 extra-base hits in what was his first full MLB season. Young earned himself an AL Gold Glove, as well.
The Bad
Much like we did for the Blue Jays, we’ll break out the OPS drop chart. More specifically, the 10 players who had the biggest OPS drops in 2026:
At the top of that list was Cal Raleigh, who had perhaps the most disappointing year (although that is very debatable) among star MLB hitters.
During an injury-shortened season, Raleigh slashed just .182/.296/.368 (.664 OPS) with 23 home runs and 38 extra-base hits. It was a stark drop-off from his 60-home-run season from 2025, one that broke numerous records. Plus, Raleigh’s production drop was a prime reason why the Mariners went from a top run-producing team to a club that finished 28th in that category this past year.
Look, injuries were a factor. That much was obvious. Raleigh missed time in the first half of the season with an oblique strain, which was actually the catcher’s first-ever IL stint. Then, there was the revelation in October that Raleigh underwent shoulder debridement surgery after the 2026 season concluded.
The positive? Raleigh had 11 home runs from August 15 through the end of 2026, tied for seventh-most in the Majors.
But Raleigh wasn’t the only hitter to have a down year. So did Josh Naylor, a former 30-home-run hitter who had just 10 in 2026. Like Raleigh, though, Naylor did undergo offseason surgery. Naylor had a wrist operation in early October.
There were other problems with the Mariners’ offense. Brendan Donovan had a hot run of the gate for Seattle. But the former Cardinal only played 39 games, as his first season with the M’s was besieged by injury.
Donovan’s injury opened up the door for Colt Emerson, whom Seattle extended before he played a game in the Majors. It was an anointment of sorts, although things weren’t hot for Emerson in his rookie season. He slashed just .190/.246/.335 (.581 OPS) with 83 strikeouts in 241 plate appearances.
While Emerson didn’t whiff a lot in the lower Minors, it gradually (and naturally) ticked up as he moved up. What happened in 2026 was more concerning: expanding out of the strike zone, more swing-and-miss out of the strike zone in Triple-A, and a lot of problems overall at the big-league level.
Moving to the pitching staff, the one real problem spot came via Luis Castillo.
Before Castillo was shipped to the White Sox, everything seemed to be on the decline. The swing-and-miss, the feel on the breaking ball, and his batted-ball metrics. For as good as Castillo was overall as a Mariner, his tenure — between friction between the club over his role and 2026 performance — ended on a sour note.
Early Projected Lineup for 2027
- C: Cal Raleigh
- 1B: Josh Naylor
- 2B: Cole Young
- 3B: Brendan Donovan
- SS: Colt Emerson
- OF: Dominic Canzone (LF), Julio Rodriguez (CF), Lazaro Montes (RF)
- DH: Luke Raley/Michael Arroyo
- SP: Logan Gilbert, Bryan Woo, George Kirby, Kade Anderson, Bryce Miller, Emerson Hancock
- RP: Andres Munoz, Matt Brash, Eduard Bazardo, Cooper Criswell, Jose A. Ferrer, Gabe Speier, Seranthony Dominguez
New Mariners manager Jason Kanzler will start off with one of baseball’s best rotations, although how long that will hold up remains to be seen. Plus, a bullpen that has experience and pitchers who’ve proven to be highly reliable.
What Kanzler and the Mariners will need is a healthier offense. The club may also need to put a lot on the plate for rookies Michael Arroyo and Lazaro Montes, both of whom arrived late during the 2026 season.
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