MILWAUKEE -- This could be quite a taxing week for the Reds' pitching staff; the club has a pair of doubleheaders scheduled for Tuesday and Saturday. Therefore, Sunday wasn’t an optimal day for starting pitcher Justin Dunn to pitch poorly.

Dunn lasted three innings during the Reds' 7-6 loss to the Brewers at American Family Field. He allowed a career-high-tying six earned runs with six hits, three walks, one hit batter and one strikeout while throwing 75 pitches. Dropping two of three in the series, Cincinnati finished its road trip 3-3.

"By the end of his outing, we realized he was not feeling well," Reds manager David Bell said. "He may have been done there anyway, but he was pretty sick at the end. He was trying to pitch through it today. I don’t think he realized how sick he was until the very end."

Entering the day, Dunn had some momentum, with a 3.20 ERA over his previous four starts.

"On the mound, he didn’t throw enough strikes. When he did, he got a little too much of the plate and was hit pretty hard today," Bell added.

Three batters into Dunn's day, Milwaukee had three hits and a 2-0 first-inning lead on Rowdy Tellez's two-run double. The Reds battled back nicely in the top of the second on Alejo Lopez's two-out RBI double and Matt Reynolds' game-tying RBI single. Lopez later added the first homer of his big league career -- a two-run drive to right field in the seventh inning -- and scored one of two runs as part of an attempted comeback in the ninth.

Dunn quickly fell into another deficit in the bottom of the second. Leadoff batter Jace Pederson was in a 1-2 count but walked and later scored on Christian Yelich's two-out RBI single. Willy Adames hit a 2-2 fastball located up and away to the opposite field for a two-run homer. The next batter, Tellez, pulled a 2-1 breaking ball towards the right-field corner for back-to-back homers, making it a 6-2 game.

In the bottom of the third inning, Dunn labored as he hit one batter and walked two more to load the bases before escaping.

Luke Farrell, who was claimed off waivers from the Cubs on Friday, was a candidate to start one game in Tuesday's doubleheader vs. the Pirates. But he was instead summoned to begin the bottom of the fourth inning.

Two batters into his first appearance for Cincinnati since 2017, Farrell surrendered Tellez's second homer of the day but finished his three innings otherwise scoreless.

“The goal of the outing was to keep it close so we’d have a chance to come back," Farrell said.

Farrell threw 59 pitches and appears unlikely to start on Tuesday.

“I’d like to think one day [off] and I can get back at it," Farrell said. "But it’s been kind of a weird week with the contract stuff and switching teams. We’ll see. I’ll try and do everything I can to recover and get back as soon as possible.”

Looking ahead, Cincinnati has Luis Cessa slated to start one of Tuesday's games. The club could look to Triple-A Louisville for the other one but has limited options.

Raynel Espinal, who was signed to a Minor League contract last month after he was released by the Cubs, is one choice: He has a 5.63 ERA in 25 Triple-A games across three organizations this season. Justin Nicolino has a 5.47 ERA in 17 games for Louisville. A lefty, Nicolino has appeared in 50 big league games -- with 33 starts -- but none since 2017.

The Reds’ No. 6 prospect, lefty Brandon Williamson, was recently out on paternity leave and hasn't pitched since Aug. 28. It's also possible for Bell to go with a bullpen day for one of the games.

Reds pitcher Hunter Greene, who has been out over a month with a right shoulder strain, could be a candidate for Saturday's doubleheader at St. Louis. However, Greene pitched only three innings with 66 pitches on Sunday in his third rehab start for Louisville after working two innings in his previous two games.

"We’ll definitely figure out how to get through it," Bell said. "Our bullpen, through everything, has really done a great job of staying available, staying ready, taking good care of themselves, so we’ll be fine. It was great that Luke was able to come in and give us three really good innings. It kept it right there for us. We know that was a possibility. We’ll figure it out one day at a time."