Mariners’ Latest Probable Starters Announcement Hints the Six-Man Rotation Is Under Review

The Mariners are leaving themselves room to rethink the plan.

May 22, 2026; Kansas City, Missouri, USA; Seattle Mariners pitcher Logan Gilbert (36) pitches during the first inning against the Kansas City Royals at Kauffman Stadium. Mandatory Credit: Jay Biggerstaff-Imagn Images | Jay Biggerstaff-Imagn Images

The Mariners didn’t officially announce the end of the six-man rotation. They also haven’t given us a clean answer. But the starting rotation is clearly under review.

Adam Jude posted Seattle’s probable starters for its upcoming series against the Baltimore Orioles at T-Mobile Park looks normal for the first two days, with the third looking rather suspicious. 

• June 16: Logan Gilbert vs. Brandon Young
• June 17: George Kirby vs. Kyle Bradish
• June18: TBA vs. Shane Baz

That TBA is doing a lot of work. If the Mariners were actually committed to the six-man rotation, this probably wouldn’t feel so mysterious. They would just line up the next arm and keep it moving.

The six-man rotation always made sense as a temporary solution. Bryce Miller was working his way back, Luis Castillo was looking shaky, and Emerson Hancock had impressed enough to earn his spot in the rotations. 

But there is a difference between having depth and letting depth overcomplicate the plan. The Mariners already tried the piggyback setup. That was never going to be a perfect long-term answer, either.

Seattle’s Rotation Depth Is Only Valuable if It Has Structure

At some point, the Mariners have to decide what they actually believe this staff should be.

Do they want the six-man rotation? Do they want to go back to a piggyback arrangement? Or do they want to move one arm into the bullpen and tighten the rotation around their best five? Those are not small questions. And this upcoming series makes it interesting.

Gilbert and Kirby getting the first two games gives the Mariners a clean start. There is no mystery there. The mystery starts after that.

This lineup has been beaten up. Cal Raleigh, J.P. Crawford, Brendan Donovan and others have all been part of injuries that have forced Seattle to survive in less-than-ideal ways. The offense has had to patch things together. So the rotation cannot become another area of unnecessary instability.

A TBA doesn’t mean the Mariners are scrapping the whole idea. They are just reviewing it because, well, they said they would.

There’s nothing wrong with using a six-man rotation for a stretch. And also, it’s fair to say that some of their best pitching days came when the piggyback plan was active. The starting six probably don’t want to go back to that, which is understandable. But the proof of concept is already there. And it worked.