Cueto, who gave up two runs and three hits over eight innings with no walks and eight strikeouts, became the NL's first 16-game winner. He is tied for the Major League lead in wins with Tampa Bay's David Price. No Reds pitcher since Jack Billingham, in 1974, had been the first in the league to 16 wins.
"He has to be in serious contention for the Cy Young, even though we don't talk about it," Reds manager Dusty Baker said. "I'm sure it's in the back of his mind, too, especially after not making the All-Star team. We feel very confident and comfortable when he is on the mound."
And there was the comfort of working in daylight for Cueto, who improved to 11-0 with a league-best 1.62 ERA in day games this season.
"I like to throw at night, don't get me wrong," Cueto said via interpreter. "But when a day game comes, I get prepared and ready, and I like to throw in a day game, too."
Besides leading in wins with a 16-6 record, Cueto is second in the NL with a 2.44 ERA and second in innings pitched with 169 2/3. He has only 37 walks, but his 135 strikeouts falls outside the top 10 in the NL.
Cueto, however, isn't ready for the Cy Young Award talk.
"I have to keep working," Cueto said. "There is a lot more baseball to go before I can think about those things."
Cueto started his afternoon by hitting David DeJesus with an 0-2 pitch and paid for it with two outs in the first inning, when Alfonso Soriano drove a full-count pitch for a two-run homer and 2-0 Chicago lead.
"I came in and I'm like 'Johnny, you gave up two, that's about it,'" Frazier said." He kept doing his thing.
"That's what he does every game. He makes us relax. He gave up a two-run home run, so what? He knows what he's doing and he'll get out of these jams and we'll do our thing at the plate."
"I'm a human being and they're going to hit me, no matter what," Cueto said. "But when [Soriano] hit that home run, I said 'OK, this is it. I'm going to stop them and I'm going to keep throwing.'"
Following the Soriano homer, Cueto retired 22 of his final 24 batters, with a pair of two-out singles only briefly denying total domination.
"I didn't know what it was. I knew he was dealing," Baker said.
After a Frazier single started the bottom of the second inning, the next batter, Xavier Paul, took Cubs starter Jeff Samardzija's 1-2 pitch deep to right field for his first homer as a member of the Reds to make it a 2-2 game. Samardzija entered the game with only four homers allowed on the road all season. He nearly doubled his total on Saturday.
In the bottom of the fourth, Frazier led off by hitting a 2-2 Samardzija pitch to left field for his 17th homer of the season. Two batters later, Miguel Cairo drove a 1-2 pitch inside the left-field foul pole for a solo homer and a two-run Cincinnati lead. Following a Jay Bruce leadoff triple in the eighth, Frazier added a sacrifice fly to his afternoon tally and an insurance run for the Reds.
Frazier enters Game 2 batting .600 (15-for-25) vs. the Cubs this season. With that kind of pain inflicted, there could be signs with his picture hanging that ban him from the Cubbie Bear near Wrigley Field.
"I don't know what it is. It's crazy," said Frazier, who also ended the Cubs' third inning with a slick defensive play at third base to rob Anthony Rizzo. "I just feel real comfortable, and confident, like I always do. When I get up there in the box, I know I'm going to do some damage. It's just the way you've got to feel, no matter who it is. When they're in town or we're over there, I feel a little more comfortable I guess."
Overall, Frazier is leading all NL rookies with 53 RBIs and is fourth in batting average(.290), second in homers and leading with five triples.
"I played against Frazier a lot in college, and I know personally, first-hand, he's a big momentum guy," Samardzija said. "He's kind of got that chip on his shoulder. He's not cocky, he's confident. And especially when he's playing well, he's really confident."
The Cubs scored one run in the ninth off of closer Aroldis Chapman after a pair of two-out hits, including an RBI single by Welington Castillo, before Chapman notched his 29th save.