MILWAUKEE -- Jonathan Lucroy was well aware of his history against Cincinnati closer Aroldis Chapman.
In five career at-bats before stepping in against the flame throwing right-hander in the ninth inning Friday night, Lucroy was 0-for-5 with five strikeouts.
"Oh, yeah," Lucroy said. "I was his first very first (at-bat) in the big leagues. He was throwing 105 because he was all excited. That wasn't cool."
Lucroy put an end to that dubious streak in dramatic fashion, belting a two-run walk-off home run in the Brewers' 7-6 victory over the Reds at Miller Park.
"That's a tough one to lose," Reds manager Dusty Baker said. "We've lost a few like that."
Chapman (3-5) had converted his last six save opportunities, but he failed to hold a 6-5 lead this time.
Khris Davis led off the ninth inning with a base hit off Chapman. Lucroy then fouled off five straight pitches, including three consecutive 99-mph fastballs, before the Brewers' catcher sent a slider over the wall in left field for his first career walk-off home run.
"You always want to be aggressive on the fastball because if he throws an off-speed pitch, your bat is going to get sped up to it," Lucroy said. "He did me a favor, really. I was fighting that fastball off he was throwing me inside. I'm sure that will be the last time that happens if I face him again."
Lucroy's homer put an exclamation point on a back-and-forth affair in which the lead changed hands three times in the final four innings.
Cincinnati's Todd Frazier homered and drove in four runs, part of a 3-for-3 night that also included a walk and a run scored. His RBI single in the seventh gave the Reds the late lead and put Chapman in position for his 31st save of the season.
"Chappy's been great all year," Frazier said. "You can't get 'em all."
Neither starter was particularly effective Friday.
Cincinnati starter Mike Leake went five innings and allowed four runs on nine hits and two walks. Alfredo Simon, Manny Parra and J.J. Hoover combined to hold the Brewers to a run on a hit through three innings before Chapman took over in the ninth.
After throwing seven scoreless innings his last time out, Tom Gorzelanny never got into a rhythm Friday against the Reds, loading the bases with two out in the first inning before Frazier started things off with a two-run single to put Cincinnati on the board.
"It wasn't a usual outing for him," Brewers manager Ron Roenicke said. "Right off the bat, you saw that the command was off. The ball-strike ratio was almost the same, which was really unusual for him. He made a couple of bad pitches that they got underneath.
"The one, actually to Frazier, the home run, I didn't think wasn't that bad a pitch. First pitch, I don't know if he was sitting on it or what. But, Tom wasn't the same."
Juan Francisco cut the lead to 2-1 in second with his 18th home run of the season. Milwaukee tied the game on Lucroy's RBI single in the third and went ahead 4-2 later in the inning on Davis' two-run double.
Frazier homered on Gorzelanny's first pitch of the fourth to make the score 4-3, and Chris Heisey's two-run home run put Cincinnati ahead 5-4 in the fifth inning.
Gorzelanny retired two of the next three batters before giving way to Donovan Hand, who worked out of the inning with no further damage.
John Axford (6-6) allowed one hit in the ninth but kept Cincinnati off the board to earn the victory.
NOTES: Milwaukee optioned RHP Alfredo Figaro to Triple-A Nashville before the game and recalled IF/OF Sean Halton. After the game, the Brewers also sent Hand to Nashville, clearing room on the roster for RHP Yovani Gallardo, who will be activated from the 15-day disabled list and start Saturday. ... Heisey's home run was his first since July 19. ... An MRI on the sprained right knee of Brewers center fielder Carlos Gomez revealed no structural damage. He's listed as day-to-day but is unlikely to return this weekend. ... Entering Friday, Cincinnati's Joey Votto and Shin-Soo Choo had combined to reach base safely in 217 of their 236 games this season. ... Roenicke said he spoke with suspended outfielder Ryan Braun Friday but was not sure when Braun would return to Milwaukee to speak to the media about his suspension. ... Before Jean Segura's RBI single in the sixth inning, the Reds' bullpen went 17 1/3 innings without allowing a run.