Kade Anderson didn’t just have a good year in the Mariners’ system. He put together one of the most dominant minor league seasons the organization has ever seen.
The lefthander worked 18 starts for Double-A Arkansas and carved through hitters with a 1.06 ERA. In 93.1 innings, he gave up 11 earned runs and 13 walks while striking out 135. That kind of run put him in rare company: only one pitcher in the modern era of the minor leagues had posted a lower ERA in a season of at least 90 innings.
That performance was enough to push Anderson to Seattle on Aug. 22.
“We had high expectations of what he was, and what we thought he was going to be able to do, and he definitely has surpassed that just with his consistency and the way he’s gone about it,” Mariners farm director Justin Toole said.
“So I wouldn’t say it was surprising, but I do think that we probably had some high expectations, none probably higher than Kade’s.”
The Mariners were thrilled to land Anderson at No. 3 overall in the 2025 draft after he led LSU to a College World Series title that season, and he wasted little time validating that belief in pro ball. With a four-pitch mix and excellent control, he held Double-A hitters to a .147 average and a 0.64 WHIP.
The jump to the majors brought a different level of resistance. In his first 21 innings against big league hitters, Anderson posted a 4.29 ERA and 1.38 WHIP with 16 strikeouts. Mariners manager Dan Wilson said the organization wasn’t rattled by the early results.
“(He’s) a guy who has prepared for a long time for these moments, and that’s why I think we’ve seen what we’ve seen from him maturity-wise over the course of his starts,” Wilson said. “I think he has settled in very quickly . . .
“Our pitching group has really done a great job, welcoming him in, and it’s just been a pretty smooth transition.”
Anderson’s rise also opened the door for others in the system. Ryan Sloan took over as the clear ace at Double-A Arkansas once Anderson moved up, and the 20-year-old delivered a five-inning gem on Aug. 22: one hit, no walks and 11 strikeouts, with the lone blemish a solo homer. Across 21 starts, Sloan logged a 3.70 ERA in 97.1 innings with 124 strikeouts and 14 walks.
At Low-A Inland Empire, Mariners 2026 first-round pick Ace Reese came out swinging. The 24th overall selection, who hit 24 homers in 62 games at Mississippi State this year, added three more in 21 games in the California League. He was batting .440/.530/.667 with eight doubles and 19 walks.
The Mariners also saw Michael Arroyo reach the majors on Sept. 6. The 21-year-old second baseman/left fielder hit .283 with an .830 OPS and 18 homers between Double-A Arkansas and Triple-A Tacoma before making his MLB debut, where he batted eighth, played second base and went 0-for-3 with a strikeout.
Lazaro Montes arrived in Seattle on Sept. 1 after blasting 38 homers and driving in 96 runs in 123 games between Double-A and Triple-A. He singled in his first at-bat at Fenway Park, then followed it with his first major league homer, a 407-foot shot to center.
On Sept. 8, he went even bigger, launching a 474-foot homer that stands as the longest home run at T-Mobile Park in the Statcast Era since 2015. His strikeout rate is still a hurdle, but the power is obvious.
And catcher Boston Smith has kept hitting since joining the organization in the Sept. 1 Luis Castillo trade with the White Sox. In 28 games with Arkansas, Smith put up nine homers, 22 walks and a .924 OPS.
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The sting only grows when the focus turns to what comes next, because the Mariners do not have the cushion of obvious young breakthroughs to soften the blow. Passan pointed to the contrast with the Mets, who at least have a wave of promising rookies and some future optimism, while Seattle is staring at looming free agency questions after a year that failed to end in the postseason. For a team that had already set the bar high, the letdown is one thing. The possibility of losing ground from here makes it feel even worse. [Read more 🡒]
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Mariners Could Face A Much Bigger Randy Arozarena Problem This Winter
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The Red Sox are already mentioned as a possible front-runner, and the possibility of a big contract puts Seattle in a difficult spot even before the offseason officially gets rolling. If Arozarena leaves, the Mariners will need to weigh a wide range of alternatives, from free agents such as Seiya Suzuki or Ian Happ to trade possibilities like Gunnar Henderson, Elly De La Cruz and Ronald Acua Jr., which tells you just how big the hole could be if they lose him. [Read more 🡒]