MILWAUKEE -- Jordan Lyles is joining the Brewers for a pennant race for the second straight year, but the circumstances are a lot different this time around.

Unlike last August, when the Brewers claimed Lyles from the Padres’ waiver wire for depth and pitched him sparingly out of the bullpen, the 28-year-old right-hander is needed immediately to fortify a starting rotation that was down to two healthy pitchers as of Monday’s trade that sent Minor League right-hander Cody Ponce to the Pirates for Lyles.

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Lyles was scheduled to start for Pittsburgh Monday night in Cincinnati. Instead, he will travel to Oakland on Tuesday to join the Brewers, who did not immediately announce which day they would slot him into the rotation.

“I know -- a lot of people know -- that Milwaukee needs some help arms-wise with how many injuries they have had throughout the season,” Lyles said. “Time will tell, but I’m definitely looking forward to it.”

The return to the Pirates was 25-year-old Cody Ponce, a 2015 second-round Draft pick in his first season as a full-time reliever. President of baseball operations David Stearns said he’d been in talks with the Pirates about multiple fronts over the past week.

Lyles made 11 appearances for the Brewers during the second half of last season after Milwaukee claimed him on Aug. 5. The Brewers declined his $3.5 million club option for 2019, and Lyles signed with Pittsburgh, where he was 5-7 with a 5.36 ERA in 17 starts, pitching most recently on Wednesday against the Cardinals.

He has not been effective lately. Since posting a 1.89 ERA in his first nine appearances (eight starts), Lyles went 1-6 with a 9.57 ERA in his last nine starts, including 0-2 with a 6.00 ERA (10 earned runs in 15 innings) in three June starts, all against the Brewers, and 0-3 with a 15.00 ERA in four July starts. He has not cleared the second inning in two of his last three outings, including last week’s 1 2/3-inning, eight-run (five earned) performance against St. Louis in a 14-8 Pirates loss.

Asked why the Brewers were interested in a pitcher preforming so poorly, Stearns said, “As we looked at the entirety of the season, both earlier and the more recent outings, we think that the underlying aspects of his performance -- what he is actually doing on the mound -- have remained fairly consistent. So we think that he is a quality addition to the club and we look forward to him contributing down the stretch here. …

“I think this happens from time to time for pitchers throughout the course of a season. It can steamroll a little bit. Clearly, Jordan has had a couple of challenging outings over the last month. We look at it as likely he’s had his three worst outings clumped together here. But the stuff is still strong. He’s still executing his pitches. And we believe that he can have success over the next two months of the season.”

Lyles called it a boost that the Brewers wanted his services in spite of recent results.

“That’s certainly how I’m going to look at it,” he said. “I’m definitely looking forward to a change. This last month or two hasn’t gone in my favor. I’ve pitched poorly. We got off to a really good, hot start, and we kind of faded off. Some injuries here and there. But execution-wise, it has been very poor. [The trade provides] new scenery, a new boost of confidence, and we’re right in the middle of another race.”

Said Pirates manager Clint Hurdle: “I think he’s shown himself enough of what he needs to do to do well when he starts and, when it doesn’t work, sometimes we can get stuck with, ‘No, that’s what I need to do. I need to hold onto that or keep going.’

“I don’t know for sure. I know that he learned a lot, he kept talking about making adjustments, he kept talking about finding something that worked and stabilizing it. It never was from a lack of preparation or lack of work. 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. I thanked him on the phone today. … The way he showed up and prepared and poured into his teammates, clubhouse, dugout, all of it -- the guy was a pro. He gave us everything he had. Some days, it was really good. And some days, it wasn’t as good.”

The Brewers were down to two healthy starters before the trade, with All-Star Brandon Woodruff and Opening Day starter Jhoulys Chacin on the injured list and Gio Gonzalez in limbo for his next start after experiencing shoulder tightness in his outing against the Cubs on Friday.

Since Lyles won’t be available until Wednesday at the earliest, and barring another outside acquisition, Adrian Houser is a candidate to start Tuesday’s 9:07 p.m. CT series opener against the A’s.

The Brewers designated Marcos Diplan for assignment to make room on the 40-man roster for Lyles. Diplan is No. 21 on MLB Pipeline’s list of Milwaukee’s top prospects.

“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 the Major League season,” Stearns said. “We certainly know every single year you’re going to go through 10-12 starting pitchers. To some extent, I think we worked through that depth, for a variety of different reasons, faster than I would have anticipated, but the unexpected happens every year. It just happens that this year it seemed to happen in [the starting pitching] realm.”