As the Seattle Mariners prepare for spring training, it’s a great time to reflect on the flurry of roster moves they’ve made this offseason. The front office has been diligently reshaping the team, making strategic decisions aimed at bolstering the roster for the upcoming season. Let’s delve into these transactions and their potential implications for the Mariners’ 2025 campaign.
In early November, the Mariners made a notable addition by promoting right-handed pitcher Blas Castaño from Triple-A Tacoma to the 40-man roster. Castaño, a 26-year-old sinkerballer, has been recognized for his potential to contribute both as a starter and reliever. His inclusion in the 40-man roster not only protects him from the Rule 5 Draft but also signals the organization’s belief in his readiness to make an impact at the major league level. Fans are eager to see how his sinker-slider combination will fare against big-league hitters.
Concurrently, the Mariners reinstated right-handed pitchers Matt Brash and Jackson Kowar, along with utility player Sam Haggerty, from the 60-day injured list. Brash, known for his electric stuff and high strikeout rates, is anticipated to play a pivotal role in the bullpen. Kowar, acquired in a trade earlier in the year, provides additional depth to the pitching staff. Haggerty’s versatility allows him to cover multiple positions, offering manager Dan Wilson flexibility in lineup construction.
As the offseason progressed, the Mariners faced decisions regarding arbitration-eligible players. On November 22, they chose to non-tender infielder Josh Rojas, utility player Sam Haggerty, and right-handed pitchers Austin Voth and JT Chargois. Making all four players free agents and freeing up approximately $8 million in payroll. The decision to part ways with Rojas, who had a projected arbitration salary of $4.3 million, was particularly surprising to some fans, given his contributions in the previous season. However, the front office likely weighed his performance against the financial flexibility gained, aiming to allocate resources more effectively.
In a bid to strengthen their infield depth, the Mariners acquired first baseman Austin Shenton from the Tampa Bay Rays on November 19 in exchange for cash considerations. Shenton, a promising prospect with a solid minor league track record, adds a left-handed bat to the organization. His progression through the minors has been marked by a keen eye at the plate and developing power, making him a candidate to contribute at the major league level in the near future.
The Mariners’ activity continued into the new year. On January 14, 2025, they acquired utility player Miles Mastrobuoni from the Chicago Cubs for cash considerations. Mastrobuoni, 29, offers versatility with the ability to play multiple infield and outfield positions. While his major league batting average stands at .219, his defensive flexibility and speed on the bases provide valuable depth to the roster.
Their most significant move came just a few days ago, when the Mariners signed infielder Jorge Polanco to a one-year contract worth $7 million, including a mutual option for 2026 based on plate appearances. Polanco, 31, is expected to primarily occupy third base. Despite a challenging 2024 season marred by injuries, the Mariners are optimistic about his return to form. When healthy, Polanco has been a consistent offensive contributor, and his switch-hitting ability adds balance to the lineup.
To make room for these additions, the Mariners designated left fielder Cade Marlowe and left-handed pitcher Jhonathan Díaz for assignment. Díaz subsequently elected free agency, while Marlowe was outrighted to Triple-A Tacoma. These roster adjustments reflect the organization’s efforts to manage the 40-man roster effectively while retaining depth in the minor leagues.
In the pitching department, the Mariners acquired right-handed pitcher Casey Legumina from the Cincinnati Reds in exchange for cash considerations. Legumina, known for his solid fastball and developing secondary pitches, adds to the organization’s pitching depth. While he may start the season in the minors, he could be a valuable asset as the season progresses, especially given the inevitable pitching needs that arise during a long campaign.
The Mariners also extended minor league contracts with invitations to spring training to several players, including right-handed pitcher Luis Castillo and catcher Julio Rodríguez. These signings aim to bolster organizational depth and provide additional options during spring training. Castillo’s experience and Rodríguez’s defensive skills behind the plate will be closely evaluated as the team finalizes its roster.
As spring training approaches, the Mariners’ roster is taking shape with these strategic additions and subtractions. The front office’s efforts reflect a commitment to building a competitive team for the 2025 season. Fans will be eager to see how these moves translate on the field as the Mariners aim to make a strong push in the American League West. The blend of seasoned veterans and emerging talent sets the stage for an intriguing season ahead.
It’s evident that the Mariners have been deliberate in their approach, balancing immediate needs with long-term goals. The acquisition of players like Polanco and Mastrobuoni addresses current roster gaps, while the addition of prospects such as Shenton and Legumina underscores a commitment to sustained success. The decision to part ways with certain players, though difficult, highlights the organization’s focus on financial flexibility and roster optimization.
Here’s the thing folks: While they didn’t make a blockbuster move, the Mariners focused on refining the roster, improving depth, and shoring up weak spots that held them back last year. These calculated adjustments may be enough to bridge the gap between second place and a division title. The AL West remains highly competitive, with powerhouses like the Houston Astros and Texas Rangers still formidable opponents. However, if these acquisitions deliver as expected—providing more consistency at the plate, a deeper bullpen, and better overall roster balance—the Mariners could position themselves as serious contenders to win the division outright.
With that… For fans in Seattle, the expectation isn’t just another strong season—it’s finally taking that next step to the top of the AL West. The front office has done its part to make incremental improvements, and now it’s up to the team to execute on the field. With spring training days away, all eyes will be on how these pieces come together in the pursuit of a division crown.
If you cannot play with them, then root for them!