For a 50-game stretch during the 2025 season — from early June to mid-August — it seemed like the Mariners had found their second baseman for the next several seasons.
Rookie Cole Young, who was called up May 31 after only 54 games at the Triple-A level, seemed to be finding his footing at the major-league level.
During that stretch of games, Young posted a .281/.369/.399 slash line with seven doubles, a triple, three homers, 18 RBI, 20 walks and only 28 strikeouts in 178 plate appearances.
But Young couldn’t sustain that stretch of success. While the Mariners pushed their way to the American League West title, Young’s production started to diminish. The league had adjusted to him and his approach, and he couldn’t seem to make the counter move to find success. With games growing in importance, the Mariners started playing veteran Jorge Polanco at second while using Leo Rivas as his backup.
When Young singled off Clayton Kershaw in his second at-bat of the final game of the regular season, it snapped a streak of 22 plate appearances without a hit. It was just his third hit in his final 59 plate appearances of the season.
Polanco, who was brought back on a one-year, free-agent contract to play third base, not his natural position, filled in ably on defense at second base and didn’t let the increased activity in the field affect him at the plate. He was one of Seattle’s best hitters down the stretch. Over the final 33 regular-season games, Polanco posted a .333/.379/.667 slash line with 16 doubles, eight homers, 25 RBI, 10 walks and 23 strikeouts in133 plate appearances.
But given his strong season, Polanco has declined a $6 million player option for the 2026 season, according to a team source, that vested during the 2025 season. He can certainly earn more on the open market as a free agent.
While there is strong mutual interest between the Mariners and Polanco in a return for 2026 and likely 2027, there is no guarantee he won’t take a better offer. Even if he were to return, the Mariners would also limit his usage at second base given his age (31) and injury history (knee surgery last offseason, oblique issues during last season).
If Polanco signs elsewhere, it would mean that some combination of Young, the switch-hitting Rivas and Ryan Bliss, who missed most of last season with a torn biceps and later a torn meniscus, both requiring surgery, would assume the duties at second base.
But could they shop the free-agent market to find a more established replacement?
The free-agent class for second baseman isn’t strong, which is another reason Polanco declined his option. Of course, shortstops such as Bo Bichette and Ha-Seong Kim could be viewed as second basemen, but both are expected to be looking for opportunities to play shortstop.
Here’s a look at who’s available:
The top tier
Gleyber Torres
Jorge Polanco
Torres signed a one-year, $15 million prove-it contract with the Tigers after not finding much interest on the free-agent market last offseason. He was named to the AL All-Star team after posting a .281/.387/.425 slash line with 16 doubles, nine homers and 45 RBI in the first 81 games. But he was abysmal in the second half, posting a .223/.320/.339 slash line with six doubles, seven homers, 29 RBI and 55 strikeouts in his last 61 games of the regular season. But there was a reason for the struggles. He was playing through a sports hernia, which required surgery a few days after the Mariners eliminated Detroit from the postseason.
Would the Mariners pivot to Torres if they fail to sign Polanco? He’s going to be looking for at least three years with an average salary between $13 million-$16 million. It doesn’t seem like an investment that would interest the Mariners.
Platoon fits (age in parentheses)
Willi Castro (29) — The Mariners had some interest in trading for the switch-hitting Castro at the deadline. He’s versatile enough to play second or third and both corner outfield spots. Given his struggles after the Twins traded him to the Cubs, Castro might be looking for a one-year deal to reestablish his value.
Amed Rosario (30) — The veteran infielder is best used as a platoon player. He has a career .298/.336/.464 slash line in almost 1,200 career plate appearances vs. left-handed pitchers. He would fit a platoon well with Young and the Mariners likely wouldn’t have to make a major financial commitment to Rosario.
Isiah Kiner-Falefa (31) — A solid veteran that brings bat-to-ball skills that the Mariners could use from any utility player. He would be low-cost option to work in a platoon with Young, while also bringing a veteran presence.
The rest
Jose Iglesias (36), Dylan Moore (33), Luis Rengifo (29), Nicky Lopez (31), Brendan Rodgers (29), Adam Frazier (34), Coco Montes (29), Cavan Biggio (31) and Kyle Farmer (34).