CINCINNATI -- Jordan Lyles is heading back to the Milwaukee Brewers, who are desperate for starting pitching as they try to repeat as NL Central champions.

The Brewers acquired the right-hander from the Pittsburgh Pirates on Monday for pitching prospect Cody Ponce, giving them a familiar name in their injury-depleted rotation. Lyles has struggled since the end of May.

"I'm definitely looking forward to a change,'' Lyles said during a conference call. "This last month hasn't gone in my favor. I've pitched poorly. We got off to a really good start, hot start, and kind of faced after some injuries here and there.''

Lyles worked out of the bullpen for Milwaukee last fall, going 1-0 with a 3.31 ERA in 11 appearances for the Brewers while helping the club win the NL Central title. Lyles translated his success with Milwaukee into a one-year contract with the Pirates and earned a spot in the starting rotation out of spring training.

He won five of his first six decisions, and then fell into a deep slump. He had a 9.58 ERA in eight starts since the end of May, leaving him 5-7 overall with a 5.36 ERA.

"It was never for a lack of preparation or a lack of work,'' manager Clint Hurdle said. "There's still enough career in front of this guy to find out whether his niche is as a starter or whether his niche is in the bullpen.

"He gave us everything he had. Some days it was really good, some days it wasn't as good.''

The Brewers were a game behind division co-leaders St. Louis and Chicago on Monday, but their rotation has been decimated in July. Milwaukee All-Star right-hander Brandon Woodruff went on the injured list with a strained left oblique and right-hander Jhoulys Chacin was sidelined by a strained muscle in his side. Left-hander Gio Gonzalez developed a tight shoulder in the seventh inning of his start Friday against the Cubs.

"I think every season takes its own twists and turns, and every season brings up unexpected situations and circumstances,'' general manager David Stearns said. "Certainly, we went into the season with what we thought was a very deep pitching staff with numbers we thought could help us get through the rigors of a major league season."

Lyles was scheduled to start Monday against the Reds in Cincinnati when he was dealt. Alex McRae (0-2, 7.71) was picked to take his place. Hurdle isn't sure who will fill Lyles' spot in the rotation long-term.

Pittsburgh could be involved in more deals as the Wednesday trade deadline approaches. The Pirates had lost eight straight and were 2-14 since the All-Star break, slipping behind the Reds into last place in the NL Central.

Ponce, a second-round pick in the 2015 draft, is 1-3 with one save, 44 strikeouts and a 3.29 ERA in 27 appearances at Double-A Biloxi this season.