"They always say that the double play is a pitcher's best friend," manager Ned Yost said. "We struggled all day long with our command. Any time you walk 10 guys and only one scores, double plays are coming up huge for you.
"I didn't know how Manny was going to get through two innings, let alone five. I just had to put my seat belt on and get through it. The defense is what won us a ballgame today."
Rickie Weeks, who returned from the disabled list for Sunday's game, had a big first day back. He was right in the middle of four of the double plays and drew a walk in the fifth inning to move the eventual go-ahead runner over to second base.
"I had to be ready [to play] sometime, and it worked out pretty good," Weeks said. " "Pitchers go up there ... trying to throw strikes, and sometimes they don't have their best stuff.
"So when they get a ground ball, it's our job behind them to turn the double play."
The victory clinched the series for the Milwaukee, wrapped up a 6-3 homestand and extended the team's hot streak. Since May 20, the Brewers have the best record in all of baseball, at 21-10.
"We're rolling on all cylinders for the first time right now," said Bill Hall, who hit a solo homer in the fifth inning. "We knew that it would happen eventually, and now we're playing really good baseball."
The Orioles jumped out to an early 2-0 lead against Parra (7-2) and then a 3-2 lead later in the game, but it didn't take long for the Brewers' offense to strike back either time.
Corey Hart hit a two-run homer in the second inning to tie the game at 2, and Hall's shot tied the game at 3 before the Brewers took the lead on an RBI single by J.J. Hardy.
"It's no secret that we hit home runs," Yost said. "It was just a matter of time before we started hitting them in big numbers. We're a home-run-hitting team."
Prince Fielder had his second multi-homer game of the season, belting two into the bleachers in right field to tack on three insurance runs in the sixth and seventh innings. The Brewers racked up seven runs on nine hits -- four of them home runs -- in the first seven innings of the game.
"When you score a lot of runs, you're going to have a lot of success," Fielder said. "I was just trying to see the ball well and hit it. I got lucky, and they went over the fence. Maybe a little skill in there somewhere."
Parra ended up allowing three runs on five hits over five innings, striking out one and walking six. Baltimore's Garrett Olson (5-3) took the loss after allowing the Brewers' first four runs over five innings of work.
"I didn't really ever find the zone, but I just kept battling," Parra said. "In games like this, the offense needs a lot of credit. They were able to take the game back over and give us the momentum."
Milwaukee's bullpen -- Mark DiFelice, David Riske, Guillermo Mota and Salomon Torres -- pitched four scoreless innings to seal the win for Parra. The Orioles were forced to use six relievers, who allowed three runs over four innings of work as the Brewers piled on.
Torres recorded his 12th save by recording the last two outs of the ninth inning. He is now 11-for-11 in save opportunities since he took over the closer's role.
The Brewers closed out the homestand with their 13th sellout of the season at Miller Park, drawing 43,517 to the series finale. Yost praised the level of fan support that his team receives on a daily basis.
"Our fans are a big part of what we do," he said. "You can't go anywhere in this town anymore without seeing somebody wearing Brewers stuff. The excitement that this team had generated last year and this year and the fun that it brings is part of the reason that I wanted to come here."
"I wanted to bring that back."