5 Mariners on thin ice who'll have the most to prove during spring training

The whole tone of spring training is going to be different for the Seattle Mariners this year. Whereas they entered 2025 as a playoff hopeful, they begin 2026 with their eyes firmly on the World Series.

That said, the Mariners will have quite a few questions to answer this spring. Let's dive deeper into those by looking at a handful of players who will begin camp on thin ice, and who must prove themselves worthy of various roles.

5 Mariners who'll have to prove themselves in spring training

Victor Robles, RF

After coming out of nowhere (well, technically Washington D.C.) to become a key cog for the Mariners in 2024, Robles' experience in 2025 was marred by misfortune and tragedy. He suffered a brutal injury early in the year that took a long time to recover from. He also lost his mother during the season.

The Mariners seem to be leaning toward using the right-handed-hitting Robles in a platoon role, but the team must surely have higher hopes. With a strong enough spring, he stands to not only lock down an everyday job in right field, but potentially a return to the leadoff spot.

Luke Raley, RF/1B

Raley was also hit hard by injuries last season, playing in only 73 games and suffering a 152-point drop in his OPS relative to 2024. It was so bad that it was somewhat of a surprise when the Mariners even chose to tender him a contract for 2026.

And yet, Raley averaged a 127 OPS+ and 21 home runs across the 2023 and 2024 seasons. If the left-handed swinger gets back to that kind of offensive quality this spring, he could at least earn the better half of a platoon role with Robles in right field. Raley would otherwise stand to take at-bats from Dominic Canzone at designated hitter.

Ben Williamson, 3B

Unless they re-sign Eugenio Suárez, the Mariners are planning to stage a competition between Williamson and top prospect Colt Emerson for the third base gig. Williamson has the glove to win the role, while Emerson will be riding a wave of escalating hype after a brilliant 2025 season in the minors.

The stakes for the two are different, though. Given his youth (he's only 20) and the fact that he only has six games at the Triple-A level, Emerson will basically be playing with house money this spring. Williamson may only have so many shots remaining at a big league job with the Mariners, who have challenged him to show off the power he developed late in 2025.

Cole Young, 2B

The Mariners are reportedly still high on Young, and they should be. He was a top-100 prospect when he debuted with Seattle last summer, and he had a multi-week run as one of the team's better hitters.

Yet if the Mariners were truly committed to Young at the keystone, there wouldn't be rumors linking them to Brendan Donovan and other infield trade targets. And even if none of those come to fruition, Young will still have to stave off Leo Rivas and Ryan Bliss to avoid a ticket back to Tacoma.

Jackson Kowar, RHP

The Mariners' bullpen has some weak links at the back end, but Kowar seems like the weakest after the club's trade for Cooper Criswell bumped Casey Legumina from the likely depth chart. Formerly a top prospect, Kowar is now a 29-year-old with an 8.21 ERA in 54 career appearances in the majors.

The velocity is there on his fastball, which gets up into the high 90s. Yet if he wants to make the Opening Day roster, he's going to have to miss bats after fanning just 15 hitters in 17 innings with Seattle last year. If he doesn't, Legumina, Troy Taylor and Alex Hoppe are among those who could take his spot.