Mariners are preparing their fans for an epic third base position battle

The Mariners have been busy this winter. After signing Josh Naylor and trading away Harry Ford, their most recent move was to get Cal Raleigh a new understudy now that Mitch Garver has returned to the open market. The front office still has plenty of work to do, however, and there are a couple of positions that many would expect them to reinforce heading into 2026.

Third base seemed like one of those positions. Since Eugenio Suárez returned to free agency, it was assumed that Seattle would be in market for a corner infielder who would add more pop to the lineup. At the beginning of the offseason, there was fan interest in NPB sluggers Kazuma Okamoto and Munetaka Murakami, but their lack of defensive viability has seemingly pushed the team in another direction. There were reportedly negotiations with other marquee players, but it seems like the Mariners will turn to their homegrown talent to fill the position.

Seattle is ready to hand over the reins at third base to one of their young prospects

According to a report by Adam Jude of The Seattle Times, Jerry Dipoto and Justin Hollander want to make sure they're making the most out of their talented group of young infielders. Rather than having them play secondary roles to established veterans, giving the likes of Ben Williamson and Colt Emerson more chances at big league playing time is the final major step of their player development arcs.

Williamson was called up early last year after it was clear that Jorge Polanco didn't have an arm that was effective enough for third base. He played admirably, although his offensive production put a damper on his strong defensive showing. His 76 wRC+ ultimately led the Mariners to make a big trade deadline move to bring Suárez back.

Williamson had a much better time at the plate with Triple-A Tacoma, posting. a135 wRC+ from August 1st through to the end of the season. His ISO of .183 was a significant improvement over the .058 ISO he posted in the majors. If he's able to carry that power into next season, he could be exactly what the Mariners need.

As for Colt Emerson, there's a reason he is the No. 9 prospect in MLB this year. He spent most of his year with High-A Everett and hit a real stride in the last few months of the season, posting a 133 wRC+ in Double-A and making 27 strong plate appearances in Triple-A. Described as having the best tools in the Mariners system, the 20-year old could debut as soon as next year and it could be at third base.

His primary position is listed at shortstop, which is where he's spent the lion's share of his playing time in the minor leagues thus far. But with a good arm and strong athletic base, moving over to third base might not be too much of an ask. He played nine games in the hot corner in 2024 but spent just two games at third in 2025. This could also be a chance to give Emerson a taste of the big leagues in preparation for J.P. Crawford's free agency in 2027 and based on his admittedly short stint in Triple-A, he's absolutely ready for a step up in competition.

The Mariners are still far from calling it an offseason. They recently lost out to the Mets in a bid to bring back Jorge Polanco, so don't let this convince you that the roster as is will be the same one that takes the field on Opening Day. But with a renewed focus on letting their young talent take the big stage, third base is one of the items they're likely crossing of their Christmas list.