Kirby (shoulder) set for rehab start; Gilbert (elbow) continuing to build up

SEATTLE -- The Mariners are continuing to progress in the direction that they were hopeful for on their two sidelined All-Star starting pitchers, general manager Justin Hollander shared on Friday.

George Kirby will make another rehab start for Triple-A Tacoma on Saturday at Cheney Stadium, then at least one more after. Logan Gilbert -- who again played catch before Seattle’s 6-3 series-opening loss to Toronto -- could throw off a mound by the end of this six-game homestand.

The club has been optimistic about both pitchers returning by the end of this month, and the latest development would align with that trajectory.

Kirby threw 42 pitches and looked electric in his rehab debut last Sunday; he should progress beyond 60 pitches, then near 80, after which he could return.

There might’ve been consideration for that second start to be in the Majors instead and have him on that shorter leash. But there’s also a competitive aspect, and the fact that Kirby made only one Cactus League start before being shut down with right shoulder inflammation.

“Not having experienced a lot of things that you would experience over a typical Spring Training,” Hollander said, “and building up -- not just the ability to go through 75 or 90 pitches in the outing, but then how that makes you feel, and being able to repeat it the next time five days later is important.”

Moreover, Kirby will be pitching on five days’ rest (an extra day than standard), which is likely the routine that he’ll operate on upon returning, as the club plans to work around its three off-days in June before a lengthy stretch leading into the All-Star break with minimal off-days.

“I want to say in the next like 45 games, it's something like more than 75 percent of our starts will come with an extra day,” Hollander said. “So I don't think we need, like, two extra days for everybody, but I think everybody will be thrilled to have the extra day most of the time from now until mid-June.”

Gilbert was seen going through his progression at T-Mobile Park on Friday, playing light catch in a windup in the outfield then going through a windup in the bullpen but without a baseball. He was throwing up to 120 feet this week in West Sacramento and began throwing last Friday in Arlington, only one week after he suffered a mild right flexor strain.

Because he was stretched out much more, it’s possible that Gilbert won’t need as many Minors starts, whenever that rehab assignment begins. Typically after a bullpen session, pitchers will throw to live hitters, then begin rehab, though every case can be unique.

“It's kind of day to day,” Gilbert said earlier this week. “We'll see. So I don't really know where the finish line is at necessarily. But it’s kind of like, I feel good.”

Hollander also shared updates on other injured players:

RHP Trent Thornton (appendicitis)
The reliever was placed on the 15-day IL (retroactive to Tuesday) with the non-baseball issue, which he underwent surgery on during Thursday’s off-day. Hollander estimated a recovery of at least three weeks.

“Some of that will be determined by how quickly he can resume throwing, from what I understand,” Hollander said.

OF Luke Raley (oblique strain)
The slugger played catch in the outfield on Friday and said in passing that things are “getting better,” which is a significant improvement from the notable pain he had been experiencing. Raley’s timeline when suffering the injury on April 29 was at least six weeks.

“Sometimes with the waist, especially as hard as Luke swings, you want to balance how he's feeling with risking re-injury,” Hollander said. “So it'll be a while still, but he's progressing really well.”

Raley will head to Arizona after this homestand to rehab at the club’s Spring Training facility.

OF Victor Robles (fractured left shoulder)
Robles will undergo a CT scan in about two weeks to make sure everything is healing well.

“If it is, then he can start the strengthening process,” Hollander said. “My understanding from talking to our medical people is that it's strength and mobility that need to happen over the next six weeks from that point. When you're immobilized for that long, when you have that traumatic type of injury in your shoulder, it just takes time for those to come back.”

So far, everything has been in line with the roughly 12-week timeline from when he suffered the injury on April 6.