Kodai Senga set to begin rehab assignment with his Mets injury return getting closer

While the Mets bullpen continues to dwindle, the starting rotation room likely will soon need to shuffle around for the long-awaited return of their Japanese ace.

Kodai Senga is set to begin a minor league rehab assignment next week following a bullpen session on Sunday for the last big step in his recovery from a shoulder injury.

Senga is expected to throw about 40 pitches during the assignment, but it’s not yet determined when or where he will go for the outing, manager Carlos Mendoza explained before the Mets took on the Astros Friday night.

He added the right-hander looked “good” in his live batting practice on Thursday where Senga threw two innings.

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What comes after, team president David Stearns said, is still unclear.

There is no specific timeline in mind for the Mets and the number of outings it may take for Senga to return remains unknown.

“Once we get into that rehab outing progression, we can be a little bit more specific as to what we think this looks like,” Stearns said on Friday. “We still may not know the exact number of outings it’s going to take, but I think what we saw yesterday here in a live BP session was really encouraging and taking this next step and getting him on a mound in a minor rehab game will be really good as well.”

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Senga, 31, has previously almost made it to the minor league step before but bowed out due to mechanical issues in May among other setbacks, including tricep discomfort that warranted an MRI exam and cortisone shot instead of throwing a bullpen session.

After an All-Star rookie season that almost saw finish second in Rookie of the Year voting, Senga has not seen any action this season since suffering the right shoulder injury in spring training.

Stearns said he is eager to have him back, along with Christian Scott, no matter the amount of musical chairs he will have to play with the rotation.

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That, he deems, is a “good problem to have.”

“We have more effective starting pitchers who are healthy at any given point than we have roster spots and rotation spots, then we are in a pretty good spot,” Stearns said. “I think we’re getting to that point. I think Kodai coming back will be a big boost.”

Scott returned to Triple-A Syracuse on May 30 after the rookie went 0-2 with a 3.90 ERA and 8.1 strikeouts per nine in five starts in the majors.

Senga and Scott would be among the rotation of Luis Severino, Sean Manaea, Jose Quintana, David Peterson, and Tylor Megill.

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