He still may be a candidate for the Cy Young despite his last three rocky starts, but the Reds just want to see him get back on track.
Cueto, who will make his 31st start of the season on Thursday against the Cubs, has an 8.22 ERA in his last three starts (15 1/3 innings). His 2.92 ERA is the highest it's been all season.
He pitched well in two starts against the Cubs in August, allowing two runs over 16 innings and earning two victories. The Reds' magic number to clinch the National League Central is three, and they can secure a spot in the postseason with a sweep of the Cubs or a Nationals win over the Dodgers.
Right-hander Jason Berken, acquired off waivers from the Orioles on Sept. 7, will make his second start of the season for the Cubs, who are trying to avoid 100 losses. The 28-year-old allowed six runs (two earned) on eight hits in four innings against the Pirates on Sept. 15.
After Berken's first start, Cubs manager Dale Sveum said the team's current state allows the organization to find out how players like Berken might figure into the future.
"It's an opportunity for these guys," Sveum said. "If everything stayed pat and everyone stayed healthy, we wouldn't have gotten to see some of our guys like [Chris] Rusin and [Brooks] Raley, or to be able to get some of these guys on waivers. The more pitchers you can get in an organization who have pitched in the big leagues or are capable of it, it creates competition in Spring Training and gives us a lot of different people to look at."
Berken wasn't satisfied with his first start.
"I need to get better, I have to get better, I will get better," Berken said.
Reds: Baker hospitalized with irregular heartbeat
Manager Dusty Baker left Wrigley Field before Wednesday's 6-5 win over the Cubs in 11 innings to visit Northwestern Memorial Hospital and have a chest X-ray to rule out pneumonia, and he was diagnosed with an irregular heartbeat. He will remain in the hospital overnight and have more tests performed on Thursday morning.
Baker, 63, left the stadium in street clothes just over two hours before first pitch. Bench coach Chris Speier managed the club in Baker's absence.
Before the team took batting practice, Baker was in the clubhouse chatting with a couple of players. He was seen by a member of the Cubs' medical staff before leaving for the hospital and was instructed to get some rest.
Baker, who managed his 3,000th game on Tuesday, reported that he was feeling fine after Wednesday's game.
Outfielder Ryan Ludwick was removed from Wednesday's game as a precaution with left groin tightness.
Cubs: Barney battling Reds' Phillips for Gold Glove
Technically, all National League second basemen are in the running for the Gold Glove Award. In all likelihood, though, the award will either go to the Cubs' Darwin Barney or the Reds' Brandon Phillips.
"They're both really talented defensive players and they both do it two different ways," Cubs manager Dale Sveum said of the second basemen. "The votes are in, and we'll find out in the playoffs who gets it. I know one thing, nobody has had a better year than Barney fielding the baseball."
Barney has made one error at second base this season, good for a .999 fielding percentage, and has set an NL record with 134 consecutive games without a miscue. Phillips has won three Gold Gloves, including one last year. He has made five errors and has a .992 fielding percentage.