"I just think when we show up, we're expecting to win right now, and that's a good feeling," said Ryan Freel, who started his second straight game in center field for Ken Griffey Jr. "Anybody at any particular time can help us win. We're putting everything together, and we're getting some wins."
"Sometimes, it just seems so easy," said Arroyo, who then reminisced about his days with the Boston Red Sox. "Right now, it feels very similar to how we felt in the  World Series against the Cardinals. It was like, show up at the park, and we expect to win."
Arroyo (8-2) allowed one run and scattered five hits over seven innings, striking out three. His eight wins and 2.31 ERA are both second in the NL.
"Everybody knew coming in that he was one of the better pitchers in baseball," said Reds manager Jerry Narron. "He's done more than you can ask for. He just continues to work real well for us."
"Hes just nasty," said Brandon Phillips. "I'm glad he's on my team," he added with a laugh.
Arroyo improved to 3-0 with a 1.74 ERA in three starts against the Cubs this season.
"He mixes it up well," said Cubs second baseman Todd Walker. "He's very effective. He knows what he's doing. It's almost a chess match with him, and it seems like against us, he wins most of the time."
After Arroyo gave up his only run -- a first-inning homer to Tony Womack -- the Reds' offense backed him by rocking Cubs starter Glendon Rusch (2-7) for five earned runs, including three homers, over 3 2/3 innings.
Freel gave the Reds a 2-1 third-inning lead with a solo homer, his third of the year, into the right-field bullpen. Back-to-back homers came in the fourth inning, when Phillips launched a two-run homer to left, followed by a David Ross blast to the same spot that made it 5-1.
"I'm just out there trying to produce, trying to stay in the lineup," said Phillips, who has six homers this season. "[I'm] trying to go out there and just do anything to make the team win."
Ross, Scott Hatteberg and Phillips, all acquisitions of new Reds general manager Wayne Krivsky, went a combined 3-for-8 with two home runs, four RBIs and five runs scored.
"Early on in the year, we played well, and you could feel the confidence growing," Arroyo said. "We slipped a little bit for a while in May. To come back [and] turn this thing around and be in first place in this division, it's making it easier to see the finish line."