The Mariners Just Locked In Their Opening Day Roster, And Here's Who Made the Cut

Opening day is almost here, and the Seattle Mariners have officially submitted their roster for Thursday. After a long spring training in the Arizona heat, we finally know who's heading north to start the season. There have been some surprises along the way, a few unexpected injuries, and at least one tough call in the position battles. Let's break down who made it and why some key guys won't be ready when the gates open at T-Mobile Park.

The Rotation: Hancock Steps Up While Miller Waits

The starting five is locked: Logan Gilbert, George Kirby, Bryan Woo, Luis Castillo, and Emerson Hancock. Here's the thing though, Hancock is taking the spot that was supposed to go to Bryce Miller. Miller dealt with oblique tightness in his only Cactus League start and isn't ready to roll yet. The team is being smart about it, not rushing a guy with a lingering injury. Miller still hasn't thrown with full intent in his bullpen sessions, so he'll need at least two more bullpens, one or two live batting-practice sessions, and then a rehab stint before he's back. The pitching coaches have been raving about Hancock's stuff this spring, particularly his improved velocity and his new slider and sweeper combo. For the third straight season, Hancock makes the opening day roster as a starter. This is his moment.

The Bullpen: No Surprises Here, But Limited Flexibility Ahead

The relief corps has been set since spring training started: Andres Muñoz, Matt Brash, Eduard Bazardo, Carlos Vargas, Cooper Criswell, Casey Legumina, Gabe Speier, and Jose A. Ferrer. That's eight arms. The leverage group of Muñoz, Speier, and Brash are back, and Ferrer, who came over in a trade with the Nationals this offseason, has pitched well at points. Bazardo will serve as the pivot guy between the starter and the leverage arms after his World Baseball Classic work for Venezuela. Vargas and Legumina both made the team, and here's the catch: the Mariners won't have much roster flexibility if they need a fresh reliever. Both guys are out of options, and Legumina had 48 MLB appearances last season, which made him the priority over Wilcox and Zulueta.

The Infield: Crawford and Mastrobuoni Head to the IL

Josh Naylor at first, Cole Young at second, Brendan Donovan at third, Leo Rivas as the utility infielder, and Ryan Bliss taking the final bench spot. But J.P. Crawford won't be starting the season healthy. He battled shoulder fatigue and inflammation all spring, played in just seven games, and got a cortisone injection a week ago. Even though he's scheduled to start throwing today, the Mariners will likely put him on the injured list so he can get proper field work and at bats before returning. Rivas will hold down shortstop in the meantime. Miles Mastrobuoni suffered a calf strain during the World Baseball Classic and hasn't played in over a week, so he'll need rehab games. Crawford's injury opens the door for Rivas to prove he belongs.

The Outfield: Julio and the Platoon Waiting to Heat Up

Julio Rodriguez is locked in at center, and the opening day outfield rounds out with Randy Arozarena, Victor Robles, Luke Raley, Dom Canzone, and Rob Refsnyder. That right field platoon of Raley against righties and Robles against lefties has started to heat up in spring training. This roster is ready to go. The question now is whether they can translate this spring success into wins when it matters.

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This article was created with AI assistance and reviewed by Seattle On Tap editorial staff. Always verify information with official team sources.