ST. PETERSBURG — The Tampa Bay Rays activated left-hander Steven Matz from the 15-day injured list and will deploy the 35-year-old in a bullpen role for the stretch run, manager Kevin Cash said after the club’s 3-0 win Saturday.

Matz signed a two-year, $15 million deal with the Rays last offseason and opened the season in the rotation, posting a 3.86 ERA in seven starts before landing on the injured list with left elbow inflammation. He returned but struggled to recover between outings, leading to a pair of rough starts, a move to the bullpen with mixed results and a second IL stint.

“Once things start going bad, you can start to force some things, then things snowball. That’s kind of where I was at,” Matz said. “Now, I’m feeling good, ultimately in a really good spot, and I’m excited to help the team.”

Matz made five Minor League rehab appearances for Triple-A Durham, including a pair of scoreless one-inning outings earlier this week. Cash said the club will reintroduce him with “shorter” stints in mind. The Rays have reason for optimism: Matz was especially effective in relief last season, posting a 3.05 ERA and a 1.10 WHIP in 76 2/3 innings over 53 appearances — including two starts — for the Cardinals and Red Sox.

“He did it last year and was very good,” Cash said. “Maybe we can catch lightning here with the next two months of him providing a pretty big role for us.”

To make room on the roster, the Rays optioned right-hander Chris Roycroft to Triple-A Durham. Cash called it a “tough conversation,” noting Roycroft had pitched three solid innings to record his first Major League save Friday night. “I don’t imagine too many scenarios where he’s not helping us at some point the rest of this season,” Cash said.

Shortstop Taylor Walls remained out of the starting lineup for a third straight game after jamming and hyperextending the middle and ring fingers on his left hand while diving back to second base Wednesday night in Toronto. Walls entered Saturday’s game as a defensive replacement in the ninth inning and said he was feeling “better each day” and didn’t think he’d be out “much longer,” though swelling still limits his ability to grip a bat. Ben Williamson started at shortstop for the second consecutive game. Cash said Walls likely won’t start Sunday either. “I think we can probably force it, but I don’t know how much sense that makes,” Cash said. “He’s so valuable to us.”