Now 17-7, Cueto was denied in his bid to be baseball's first 18-game winner. He remains the National League's ERA leader at 2.58, just ahead of the Mets' R.A. Dickey (2.63).
In day games this season, Cueto is now 11-1 with a 1.87 ERA. Against the Phillies, he allowed four runs on eight hits over seven innings without walking a batter, while striking out five. He gave up two home runs for only the second time this season.
It was the sequence of events before Cueto's first homer allowed that set the stage which doomed the makings of a fine outing.
Cueto retired a stretch of nine in a row -- and 12 of 13 -- until running into trouble with two outs in the fifth. Steven Lerud hit a slow roller into center field for a single, and then pitcher Tyler Cloyd followed with a grounder up the middle that went for his first big league hit.
"Every time on the bench talking to the other guys, I said, 'The outs you've got to get [are the ones against] their pitcher,'" Cueto said via an interpreter. "You always have got to get the pitcher out. I wanted to have that guy out today, but I made the wrong pitch and did not get the guy out."
Next up was Jimmy Rollins, who hit Cueto's first-pitch changeup into the right-field seats for a three-run homer.
"He's tough. He's good," Phillies manager Charlie Manuel said of Cueto. "He challenged Rollins, and Rollins hurt him. But at the same time, he's real good."
Showers fell at Great American Ball Park just as the fifth inning got started, and Cueto was struggling with his footing. After Rollins' homer, the grounds crew worked on the mound.
"It's not an excuse," Cueto said. "The guy got a hit, that's it. Just one, two bad pitches and that was it. ... That happened and you get three runs after two outs, you say 'Why did this happen?' You're supposed to get it done. I didn't get it done."
With one out in the sixth, John Mayberry Jr. hit an 0-1 slider to the first row of left-field seats for a solo homer and a three-run Phillies lead.
Cueto, who hadn't lost any of his previous five starts, has surrendered 11 home runs this season over 188 2/3 innings -- with seven coming at home. He is now 9-2 in starts at home this season.
Playing a series-opening day game on a holiday after a 5-1 road trip, the Reds sputtered against Cloyd, as he made his second big league start for Philadelphia. His only blemish was a second-inning solo homer by Jay Bruce with one out in the second. For Bruce, the shot to right field was his 30th homer of the season, and it gave Cueto a 1-0 lead.
After the Bruce homer, Cloyd retired 17 of his final 20 batters -- allowing only three more hits. He struck out nine batters, one shy of his professional career high.
"He did a lot of different things with the ball. He missed barrels," Bruce said. "He was confident with his pitches. I felt like we saw the ball fairly well. It was just enough here and there to miss the big hit or big inning."
The Reds added a run in the ninth, when Bruce drove home Ryan Ludwick with a single up the middle against reliever Phillippe Aumont.
"We had some action today, not a whole bunch," Reds manager Dusty Baker said. "It wasn't a very eventful day for us. We'll come back tomorrow."
With the Cardinals' 5-4 win over the Mets, the Reds' lead in the NL Central fell to 8 1/2 games.