Injuries to Ryan Bliss, Victor Robles, and Jorge Polanco have required the Mariners to drastically rethink their lineup in recent weeks. Bliss’s expected four-to-five month absence after undergoing surgery on his biceps leaves a hole at second base, which Polanco won’t be able to fill for at least another week or two as he’s been limited to DH-only duties by his own injuries. Robles, meanwhile, figures to be sidelined for at least three months by a shoulder fracture, which forced Luke Raley to move from first base to right field. That leaves two spots in the club’s infield that need to be filled, and while Miles Mastrobuoni and Rowdy Tellez are holding down the fort for the time being it’s hardly a surprise that the Mariners have begun exploring the market for infield help as they look to reconstruct their offense.
The idea of the Mariners searching the market for infield help is hardly a new one. Over the offseason, Seattle reportedly engaged in trade conversations regarding players like Cubs second baseman Nico Hoerner, Phillies third baseman Alec Bohm, and Red Sox first baseman Triston Casas. None of those trade talks ultimately gained enough traction for Seattle to bring an infielder into the fold, however, and so they went into the season with a largely unchanged infield aside from a minor addition in Donovan Solano. The hangup in those talks appears to have been the Mariners’ hesitation to part ways with a member of their excellent starting rotation. Seattle’s on-paper starting five of Logan Gilbert, George Kirby, Bryan Woo, Luis Castillo, and Bryce Miller is in the conversation for the very best in the entire sport, but the team’s unwillingness to split up that quintet seemed to hamper trade talks this winter even as they reportedly at least listened to offers on Castillo.
If the club was reluctant to trade from its rotation this winter, they appear even more unlikely to do so now. USA Today’s Bob Nightengale wrote this morning that one unnamed organization offered the Mariners a young infielder in exchange for Castillo in the aftermath of Seattle’s recent injury woes but was rebuffed, with Seattle indicating that Castillo is off-limits for the time being. It’s notable that the club is holding firm on its desire to keep a strong starting rotation together, even if the details about the reported trade offer are rather sparse. It’s understandable that the Mariners wouldn’t want to compromise their starting pitching depth this early in the season, even in the face of their current woes on offense, given that Kirby is currently out of commission with shoulder inflammation.
Kirby is tentatively expected to be back at some point in May, but details on his recovery process have been relatively sparse so his exact timetable for a return is unclear. Nonetheless, it stands to reason that the Mariners wouldn’t be interested in dealing from a rotation that currently features just four starting pitchers until Kirby returns unless completely overwhelmed by an offer. That’s especially true given how well Castillo has pitched so far, with a 2.12 ERA and a 3.99 FIP across his first three starts of the season.
The Yankees and Mets entered the season with a number of notable rotation injuries and could certainly benefit from a proven starter like Castillo, and injuries will surely continue to plague the rotations of contenders in the coming weeks and months. Just today, the Cubs announced that ace southpaw Justin Steele will miss the remainder of the 2025 season due to impending elbow surgery. The Red Sox, Orioles, and Padres are among the other teams that have been bitten by the injury bug in the rotation to this point in the year, though that list could obviously look very different by the time trade season kicks into full gear.