Five Seattle Mariners Prospects Who Could Contribute in 2026

Many may be confused about the potential for Anderson to be called up, given that he hasn’t thrown a single pitch at the minor league level. But alas, they have not watched LSU baseball.

At the D-I level in 2025, Anderson was a workhorse. He threw 119 innings, good for first in the SEC by a wide margin. After throwing to a 3.18 ERA and 1.06 WHIP, Anderson became one of just three pitchers in all of D-I baseball to throw at least 100 innings with a sub-4.00 ERA.

As a result of this, as well as a 5.1 K/BB ratio, Anderson heard his name called third on draft day by Seattle. While he definitely has a lack of professional experience in the minor leagues, the big key that sets him apart is his ability to throw deep into games. While many minor leaguers aren’t throwing past the fifth inning, Anderson’s 119 innings were thrown over just 19 outings.

There’s certainly a chance that Anderson spends 2026 in Double-A and Triple-A. But the last time someone went to LSU and threw at least 119 innings at that level, he started the All-Star Game and won Rookie of the Year with the Pirates the next season.

Is Kade Anderson going to put up the same numbers as a rookie Paul Skenes? Probably not. Could he be a major part of the Mariners rotation in 2026? Certainly.

INF Michael Arroyo (Just Baseball No. 84)

Arroyo is that one player that is so easy to underestimate until you watch him at the dish. He stands at just 5-foot-10 with below-average defense for the major-league level. However, one look at Arroyo in the box and you’ll see one of the most polished hitters in the Mariners’ system.

Arroyo possesses above-average power, something that could make him one of the premier power threats at a power-weak position in second base. Over the past two seasons across three minor league levels, Arroyo has clubbed a total of 40 homers.

This comes alongside plus plate discipline, with Arroyo walking over 12% of the time in 2025 and getting on base at a .401 clip before his promotion to Double-A.

Arroyo is still young, however, and won’t be someone that sees Opening Day action in Seattle. That being said, if he continues at this rate, Arroyo could be a major contributor in September and potentially the postseason, should the Mariners make it back.

LHP Robinson Ortiz

The Mariners went into the offseason needing left-handed pitching in their bullpen. With just Gabe Speier on their depth chart at the start of the offseason, Seattle acquired Jose A. Ferrer from the Nationals in exchange for Harry Ford.

But this doesn’t mean they won’t need a third lefty, especially given the sizable splits of division rival lefties like Nick Kurtz and Corey Seager. This is where Robinson Ortiz slots in.

Already on Seattle’s 40-man roster, the former Dodgers farmhand looks primed for a callup. While Ortiz’s walk rate and home run rate decreased after a midseason callup to Double-A, the issues resurfaced in Triple-A. His BB/9 went through a roller coaster across these levels, falling from 6.23 to 3.80 before rising back again to 4.96.

Despite this, Ortiz has improved mightily in 2025, and should the Mariners need someone to deal with pesky lefties in high-leverage situations, don’t be surprised to see manager Dan Wilson reach for the phone and ask for Ortiz.

SHP Jurrangelo Cijntje

This is easily the biggest stretch on the list given that Cijntje has just 33.2 innings pitched at the Double-A level. But when September rolls around, with pitchers beaten down from a season full of fastballs, why not turn to the guy who has the hand advantage over lefties and righties?

While Cijntje’s Double-A sample was quite small, he limited runs effectively, finishing with a 2.67 ERA at that level. The major flaw in his game is control, averaging 4.3 BB/9 at Double-A and 4.2 across two levels in 2025.

Aside from the slight jump in walks, Cijntje made huge strides last season after receiving the promotion to Double-A. His HR/9 plummeted from 1.7 to 0.3, with his ERA dropping nearly two runs.

Cijntje is attempting to be just the second switch pitcher in modern-era MLB history after Pat Venditte, and with his current trajectory, he could certainly get there as early as 2026. While he likely won’t settle into a starting role until 2027, a bullpen spot or even that fifth spot in a stacked Mariners rotation could be up for grabs should the Mariners experience injury troubles down the stretch.