Milwaukee let a four-run lead get away, then overcame a three-run deficit to win its fifth straight and stay within 2 1/2 games of St. Louis for the second National League wild card berth.
Pittsburgh's third straight loss dropped the Pirates a game under .500 for the first time since May 29, when they were 24-25. Pittsburgh had a 62-46 record on Aug. 6 before falling into its late-season slump.
The Brewers trailed 7-4 heading into the eighth, but Norichika Aoki doubled home a run in that inning and then scored along with Jean Segura on a triple by Rickie Weeks.
Ramirez followed with a single to center that scored Weeks with the go-ahead run. Logan Schafer added a run-scoring base hit in the ninth.
Chris Resop (1-4), the sixth of seven Pittsburgh pitchers, was charged with the loss.
Milwaukee has won 19 of its last 24 games to jump into playoff contention.