PHILADELPHIA -- Monday's series opener vs. the Phillies wasn't meant to be a bullpen day for the Reds' pitching staff, per se.

Yes, Luis Cessa has been a reliever most of his career and for all of this season -- except for one game when he was used as an opener. But amid roster moves over the weekend, Cessa was inserted into the rotation, and manager David Bell hoped the right-hander could have some quick innings and potentially stretch himself a little against Philadelphia.

But Cessa worked only two innings and was done in by back-to-back home runs in the bottom of the second as Cincinnati went on to a 4-1 loss at Citizens Bank Park.

"Overall, I think it’s not the first impression I want to [make], but I feel good," Cessa said.

Cessa, who replaced T.J. Zeuch after he made two ineffective starts and was sent back to Triple-A Louisville, allowed three hits and one walk with three strikeouts. He threw 41 pitches, which was about the pitch limit Bell had in mind for him.

It had been a week since Cessa last pitched, when he threw 18 pitches over two innings vs. the Phillies at Great American Ball Park on Aug. 15. The Reds have been shorthanded in the rotation following the trades of Luis Castillo and Tyler Mahle and an injury to rookie Hunter Greene.

That led to the choice of pressing Cessa into service as a starter for the first time since 2018, when he started five games for the Yankees.

“He’s going to have to build into it and work into it. It’s a good start to go two innings and then just build on that," Bell said of Cessa.

A 57-minute rain delay ahead of first pitch forced both Cessa and Phillies starter Noah Syndergaard to alter their pregame routines.

Cessa gave up a two-out single during a scoreless first inning, but he opened the second inning with former Red Nick Castellanos crushing a 2-0 hanging slider to center field for a homer. Two pitches later in a 1-0 count, Bryson Stott blasted a fastball that was low and inside for a no-doubt homer to the second deck in right field to make it a 2-0 game.

"He had a good breaking ball. It was really just those two pitches," Bell said. "We went into it just kind of letting him read how he was doing, how he was feeling. I think in the second inning, he had to work a little harder. He said he could go back out, but given the workload leading up to that start, it felt like pushing him wasn’t the right thing to do there."

After he was acquired from the Yankees ahead of last season's Trade Deadline, Cessa posted a 2.05 ERA in 24 appearances. It's been a tougher year in 2022, as he is 3-2 with a 5.67 ERA in 38 games.

"It’s different warmups, [sitting] down in the dugout, but I think it’s step by step … because I stayed all year in the bullpen and they moved me to a starter. I think I’ll be fine," Cessa said. "I feel excited for this opportunity, so maybe next time I’ll be better."

Offensively, Cincinnati notched three hits against Syndergaard, including Austin Romine's two-out homer to left field in the fifth inning.

The positive news is the bullpen quartet of Joel Kuhnel, Art Warren, Ross Detwiler and Hunter Strickland pieced together the rest of the game for Cincinnati, allowing two more runs while striking out nine over the final six innings.

"You know, they kept us in it. It’s not like [the Phillies] walked away with the game," Romine said. "I think the bullpen actually held a good-hitting team to four runs and gave us a chance to actually chip away. We just couldn’t find a way tonight."

Better news was the club avoided burning Alexis Díaz in a game where it trailed. Less good news is the bullpen was taxed pretty hard with six games left on the road trip and nine games to go before the next team off-day on Sept. 1.

"I don’t know how many of those guys we’ll have tomorrow. But given what they did, they gave a few of our guys a break," Bell said. "We’re actually in pretty good shape tomorrow, and we’ll just take it one day at a time.”