MILWAUKEE -- Gio Gonzalez is getting comfortable with his new team.
Manny Pina also had a three-run shot and Aguilar finished with four RBI as he reached 103 for the season. Gonzalez's stellar showing helped the Brewers boost their lead for the top NL wild card to three games over St. Louis, which lost to Atlanta earlier.
The Brewers also moved within 2 1/2 games of the first-place Cubs in the NL Central. Chicago lost 9-0 at Arizona.
Gonzalez (9-11) was acquired in a trade with Washington on Aug. 31 in an effort to bolster the Brewers' starting rotation. He has picked up a victory in two of his three starts with Milwaukee, and the Brewers have won all three games.
"It's been easy to play with these guys because they make you feel welcome," Gonzalez said. "There's no added pressure. Just go out there and play the best you can."
He allowed just two hits Wednesday -- both singles -- while striking out five and walking two.
Reds right-hander Matt Harvey (7-9), a pitcher the Brewers nearly acquired a few weeks ago before a proposed deal fell through, gave up Aguilar's game-changing home run.
Aguilar, however, said his infield hit in the first inning for his 100th RBI set up his big night.
"I was thinking about the RBI almost every night," he explained. "After that, I'm good. It was an unbelievable feeling. When I get that 100, I'm a new guy."
A leadoff walk to Gonzalez put Harvey in trouble in the third inning. Christian Yelich reached on a one-out infield hit when no one covered first base on a bouncer fielded by Harvey.
Aguilar followed with a high drive into the right-field bleachers, his team-leading 33rd home run of the season, to give the Brewers a 4-0 lead.
Milwaukee broke open the game in the sixth on a three-run homer by Pina, who worked a 13-pitch at-bat, finally belting a hanging slider from Harvey into the left-field bleachers. Domingo Santana tripled and Mike Moustakas was intentionally walked before Pina's ninth homer of the season extended the lead to 7-0.
The Reds had a conference on the mound during the long at-bat, but it didn't bother Pina.
"I was so focused, man," he said. "After they gave an intentional walk to Moose, I was like, I need to do something this at-bat. He threw me pitches inside, outside, changeups, fastballs, sliders.
"He's kind of tight. I knew he was going to hang any pitch and that's the pitch I hit for a homer."
Harvey was not happy with his outing, which dropped him to 1/3 with a 6.39 ERA in six career starts against the Brewers. He allowed seven earned runs in 5 1/3 innings.
"The whole start was not good," he said. "I have to be better."
CHASE STILL ON
Brewers manager Craig Counsell has not given up on catching the Cubs for a division title.
"We've got nine games to go," Counsell said. "We've got plenty of baseball left. There are going to be some great moments. There are going to be plenty of tough moments. That's all still ahead of us.
"We're just ready for it to happen. We've put ourselves in a great position to enjoy the last 10 days of the season."
The Brewers have six road games remaining (three vs. Pittsburgh and three vs. St. Louis) and the final three at home (against Detroit).
Milwaukee ended its homestand with a 3-3 record against the Pirates and Reds.
Brewers: CF Lorenzo Cain was not in the lineup after being taken out of Tuesday's game with a right ribcage injury. Counsell said he wanted to be cautious with Cain, who ranks fourth in the NL in batting average (.308). The Brewers are off Thursday and Cain will be reassessed before Friday's series opener in Pittsburgh. "I definitely don't want to miss a game," Cain said. "They told me that I'm not looking myself up there right now." Santana got the start in right field -- his first game as a starter since June 12 -- and Yelich moved to center with Curtis Granderson in left. Infielder Travis Shaw was back in the lineup after being hit by a pitch Tuesday and leaving the game with a bruised right knee.
Reds: LHP Cody Reed (0-2, 4.32 ERA) will make his fifth consecutive appearance as a starter as Cincinnati opens a four-game series in Miami. He posted a career-high 10 strikeouts in five innings against the Chicago Cubs on Saturday, allowing no runs and two hits in a game the Reds lost 1-0.
Brewers: RHP Jhoulys Chacin (14-8, 3.54 ERA) opens a three-game set in Pittsburgh. He has lost his last three starts, including a 3-2 defeat (allowed three hits, two runs) against the Pirates on Sunday. He is 2-6 with a 4.04 ERA in 11 career starts vs. the Pirates.
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