Milwaukee tied it up in the top of the ninth after Reds shortstop Elly De La Cruz threw it past first baseman Spencer Steer, moving the game to extra innings.
After the Brewers went up 3-2 in the top of the 10th inning, the Reds battled back in the bottom half to send the game into the 11th inning, all tied up at three runs apiece.
The run came from one of the most bizarre things fans will ever see happen during a game.
Then, just like that, Andruw Monasterio launched a three-run home run, just his second of the season, in the top of the 11th inning to give the Brewers a 6-3 lead. The Reds battled back to make it 6-5, but Milwaukee prevailed in the end.
On Friday, the Brewers battled back down from 8-1 against the Reds to eventually win 10-8 (watch here) - showing there is absolutely zero quitting from the best team in baseball.
Trevor Megill earned the win for the Brewers while Nick Mears earned his first career save.
The Brewers have outscored their opponents 119-52 during the win streak. They are 39-9 in their last 48 games, now possessing a league-best 78-44 record with a +161 run differential - leading the Chicago Cubs (+116) as the only two teams in baseball with a run differential over 100.