Analysis: How the Mariners plan to round out their rotation the rest of the season

By Ryan Divish

The Seattle Times

DETROIT — After rolling with a four-man starting rotation since the trade of Mike Leake on July 31, the Mariners will finally need to add a fifth starter to their rotation for Saturday’s game in Toronto.

But will they?

Mariners manager Scott Servais said the team is leaning toward using the bullpen to fill out the innings for that start.

“More of an old school bullpen day where there would be an opener, a re-opener, a bulk guy, then a set-up guy and all the other good stuff,” he joked. “We have to check all the boxes. But that could change.”

Indeed, the Mariners are using openers for the start on Thursday and Friday before that start, which could factor into the decision.

“It would really dictate on how this last game here in Detroit went,” he said. “But right now I think we will go with what we’ve got.”

Why do this?

Why not just call up prospect Justus Sheffield, who has been dominating since being demoted to Class AA Arkansas.

Well, there are some timing factors to take into consideration that might not work, which Servais admitted.

Sheffield is going to get an earned call-up very soon. Since being sent down to Arkansas, he’s rediscovered his confidence and command. In 11 starts, he’s 5-2 with a 1.75 ERA. In 72 innings pitched, he struck out 79 batters with just 16 walks. Of the 1,003 pitches he’s thrown with the Travelers, 68% of them have been strikes which is up almost 10% from his time in Tacoma.

He started on Sunday for Arkansas, so the time frame works if the Mariners change their mind and need a starter for Saturday. General manager Jerry Dipoto has said he would like to call up Sheffield more toward the end of the month.

If you map out the rotation, the next turn for the fifth starter would be Friday, Aug. 23 at T-Mobile Park vs. the Blue Jays, which opens the next homestand.

Felix Hernandez is not a candidate for that start on Saturday despite declaring himself ready after his rehab start last Thursday in Modesto.

Instead he will make his third rehab start Wednesday night at Funko Field in Everett. This will be Hernandez’s second start for Short-season Everett on his rehab stint.

“We need to get him stretched out a little bit,” Servais said. “I’d like to see him go at least four innings and then probably one more time out there and get him through five and go from there. That’s the goal right now.”

He’s expected to make at least one more rehab start, likely with Class AAA Tacoma before re-joining the Mariners. If he stays on normal rest, that start final rehab start would be on Monday, August 19 at Cheney Stadium.

The earliest the Mariners could insert Hernandez back into the starting rotation on normal rest would be on Saturday, August 24. That would be Yusei Kikuchi’s normal day to pitch. But the Mariners have been looking to get Kikuchi a rest day after making all five of his scheduled starts since the All-Star break. He has two starts scheduled on the current road trip. Starting Hernandez in that Saturday night game vs. the Blue Jays at T-Mobile Park would allow them to skip Kikuchi. Seattle has an innings limit between 160-170 this season for Kikuchi. He came into Tuesday with 123 innings pitched.

So if it lines up properly, the Mariners could add Sheffield and Hernandez into the rotation on the upcoming homestand and readjust as needed, possibly moving to a six-man rotation. The month of September has four offdays, which also allow them to be creative to close out the season.