Richard Fitts took the mound for Double-A Portland in his first rehab start on Thursday afternoon.

The Red Sox right-hander gave up four hits, zero earned runs and struck out two in three innings of work. Fitts threw 38 pitches, 31 of them for strikes in the Sea Dogs’ 6-3 win over the Reading Fightin Phils.

Fitts has been on the injured list since April 13 with a right pectoral strain. He threw a 40-pitch live batting practice at Fenway Park on May 17 and was pain-free afterward.

“I’m ready to get back and compete, and ready to help the team win as much as I can,” Fitts said over the weekend. “I’m super eager but I also want to make sure I’m ready whenever I get back. I don’t want to rush back and then not help the team win and go out there underperform. So I want to be as ready as I can. I think it’s close, for sure.”

Fitts’ last start for Boston came April 12 when he tossed five shutout innings with five strikeouts against the Chicago White Sox. He was quickly pulled from the game after grabbing his shoulder immediately after a pitch.

It’s unclear what the next step for Fitts will be, but whenever he’s ready he’ll be a welcome addition to the starting rotation.