Projecting Mariners’ opening day roster ahead of spring training | Analysis

In years past, the task of writing such an early opening day roster projection for the Seattle Mariners might seem difficult or foolish.

The uncertainty surrounding certain positions, the pairings for platoons — both expected or unexpected — and the possibility of Jerry Dipoto transacting in some way to affect the 26-man roster always lingered.

But it feels different this year as spring training nears.

Perhaps it’s due to an offseason that featured only two free-agent signings, a few minor trades and a handful of waiver claims that left much of the fan base disappointed if not dismayed at the relative inaction.

But Dipoto justified the decisions made and the offseason moves — or lack thereof — completed as a product of the roster certainty that developed late last season.

“We didn’t anticipate a great deal of movement around the team,” he said in a recent video news conference. “We’re still open to adding, if the opportunity to add exists out there. But we feel like this is a good team, and if this is our team going into spring training or opening day, we’re pretty excited by it.”

So let’s try and take a way too early look at the team going into opening day. The Mariners have 70 players slated to attend MLB spring training with the possibility of outfielder Cade Marlowe and left-handed pitcher Jhonathan Diaz both being added if they clear waivers and get outrighted to the Mariners minor-league system.

They will need to trim down to 26 spots — 13 pitchers and 13 position players — before opening the 2025 season March 27 vs. the Athletics at T-Mobile Park.

Starting rotation (5)

• Luis Castillo, RHP
• George Kirby, RHP
• Logan Gilbert, RHP
• Bryce Miller, RHP
• Bryan Woo, RHP

Notes: The Mariners went into the offseason with no real desire to trade from one of the best starting rotations in baseball. And despite a slew of offers for Gilbert, Kirby, Miller and Woo and listening to trade offers for Castillo, they never made a move to break up the quintet. The reasoning was simple: the hitters they might receive in return for one of their younger starters wouldn’t provide enough impact to offset what they’d be giving up in a starter. As for Castillo, the Mariners were looking for an impact major-league position player in return without taking on additional money via a salary dump. Given their limited budget flexibility, it was a nonstarter in deals.

Bullpen (8)

• Andres Munoz, RHP
• Gregory Santos, RHP
• Collin Snider, RHP
• Eduard Bazardo, RHP
• Trent Thornton, RHP
• Cody Bolton, RHP
• Tayler Saucedo, LHP
• Gabe Speier, LHP
• Injured list: Matt Brash, RHP; Troy Taylor, RHP; and Jackson Kowar, RHP

Notes: Projecting this group is always difficult given the year-to-year and even week-to-week vagaries of relief pitching production. The group that starts the season is rarely the group that finishes it. The absence of Brash and Taylor are notable. Dipoto said that they hope Brash (Tommy John surgery) is back by the end of April, which might be a little optimistic. Taylor, who made the jump from Double-A to the big leagues last season, showed plenty of talent and maturity. But a lat strain suffered during offseason throwing has put him behind schedule. He won’t be ready to go by opening day.

The rest of this projected bullpen are all currently on the 40-man roster and saw MLB time last season. Munoz is locked in as the closer. But the setup men ahead of him are less certain. Santos has the talent to be effective in that role, but he couldn’t stay healthy last season.

In seasons past, the Mariners found help from relievers claimed off waivers or signed on minor-league contracts. Of that group, Shintaro Fujinami might have the most talent. He has elite velocity with his fastball and nasty secondary pitches. But he also has minimal idea where they are going when thrown.

Infielders (7)

• J.P. Crawford, SS
• Luke Raley, 1B
• Jorge Polanco, 3B
• Donovan Solano, 1B/3B
• Dylan Moore, 2B/OF
• Leo Rivas, IF
• Miles Mastrobuoni, U

Notes: The Mariners need J.P. Crawford to bounce back from last season’s injuries and struggles at the plate. He might never replicate his 2023 season, when he posted a .266/.380/.438 slash line with 142 hits, 35 doubles, 19 homers, 94 runs scored, 65 RBI, 14.7% walk rate, 19.6% strikeout rate and 4.9 fWAR. But he certainly is better than the .202/.304/.321 slash line, 79 hits, 16 doubles, two triples, nine homers, 55 runs scored, 37 RBI, 11.5% walk rate, 22.6% strikeout rate, 1.6 fWAR he posted in 105 games last season.

The Mariners added Solano to serve as part of a platoon with Raley at first. He is also capable of playing second base and third base — though he’s not outstanding defensively at either position.

After not having his $12 million club option picked up by the Mariners, Polanco re-signed as a free agent for a 1-year, $7.75 million contract to play third base. The Mariners believe offseason surgery on the patellar tendon in his left knee will help Polanco return to previous offensive form while playing third base is a better fit in terms of his range and movement.

Moore is expected to see the bulk of the time at second base with either Rivas or Bliss filling in as needed. Could Cole Young, one of Seattle’s top prospects, take over the spot at some point in this season?

Outfielders (3)

• Julio Rodríguez
• Randy Arozarena
• Victor Robles

Notes: This was essentially the Mariners’ daily outfield for the final six weeks of last season. The trio doesn’t lack for energy, swagger or talent. Rodríguez is a perennial Gold Glove candidate in center field. While his defense has been a constant since his MLB debut, the Mariners are hoping that his offense will be more consistent for an entire season. The past two seasons, Rodríguez has gotten off to slow starts. His struggles last season carried beyond July. But slight changes to setup and swing and a simpler approach at the plate pushed by Edgar Martinez led to success in the final two months of the season.

Acquired at the trade deadline, Arozarena gives the Mariners their most experienced and proven everyday left fielder in years.

Robles’ production is far from a certainty. A once-heralded prospect for the Nationals, he was largely a disappointment in D.C. In 607 MLB games, he posted a .236/.311/.356 slash line before being released. After signing with Seattle for the MLB minimum, Robles flourished in his new surroundings, posting a .328/.393/.467 slash line with 20 doubles, four homers, 26 RBI and 30 stolen bases in 77 games. It earned him a contract extension with Seattle. Most scouts believe that Robles’ potential production is somewhere in the middle of those two extremes. He’s versatile enough to play center field if Rodríguez needs a day off.

Raley will also see some time in the corner outfield spots when needed.  

Catchers (2)

• Cal Raleigh
• Mitch Garver

Notes: Raleigh returns as one of the team’s leaders on and off the field. He is arguably the best catcher in the AL if not all of baseball. But can the Mariners continue to use him behind the plate so much? He’s caught more innings than any other catcher in baseball (2,160) over the past two seasons. Due to his struggles at the plate last season, Garver was moved from full-time designated hitter to backup catcher by midseason. Could he move back to the full-time DH role? The Mariners would have to carry another catcher if Garver were to reestablish himself as an everyday player.

Designated hitter (1)

• Mitch Haniger

Notes: This was a tough call since it seemed impossible to keep both Haniger and Garver on the roster for 2025. It became clear early last season that Haniger can’t play on an everyday basis, particularly in the field. But could he take Garver’s spot as the everyday designated hitter? Some scouts believe that a reduced role might allow him to refind his offensive production and be more of a viable contributor. It’s difficult to see the Mariners designating Haniger for assignment and eating all of the $17 million owed on his contract without at least trying to find some value from the situation.