The outfielder belted a go-ahead home run off Jean Machi in the seventh inning and made a sliding catch in foul territory that helped squash an eighth-inning Giants' rally.
"It was certainly important on both ends," Brewers manager Ron Roenicke said of Parra's efforts. "The defense, we know, he's a Gold Glover, what kind of arm he has. We know he has range out there. He's shown he has a good feel for where he is in the field. Offensively, we always thought he was a tough out. If you make really good pitches on him, we're comfortable, but with the mistake pitches, he'll battle well. It was good to get that hit today. He's been trying to get a big one for us, and that was huge."
Parra's first hit in a Brewers uniform helped delivered a victory in the opener of a difficult six-game homestand. It also helped keep the Brewers in sole possession of first place, one game ahead of St. Louis, in the National League Central race.
But perhaps even more important than the longball was Parra's catch down the left-field line in the eighth inning. Brewers relievers Will Smith and Jeremy Jeffress had put two runners on base with walks with only one out in the inning. With Jeffress pitching, Brandon Crawford sent a fly ball into foul territory in left field. Parra, filling in for regular left fielder Khris Davis, sprinted to the ball and slid near the side wall to make the catch.
"To make a homer, that's perfect. But I think the catch is better," Parra said. "The catch was big because there was first and second and one out. When I catch the ball, everybody feels better and [Jeffress] can feel more comfortable on the mound."
"Huge play. I like Khris Davis in left field, he does a really nice job, but I don't think Khris Davis probably gets to that ball," Roenicke said. "It's just a matter of foot speed. Parra runs well. He did a great job knowing where he was with the wall and going to that little slide there. Not many left fielders are going to make that play."
Jeffress struck out Buster Posey to end the inning. Francisco Rodriguez came on in the ninth to record his 33rd save, with the game ending on an overturned safe call at first base.
The challenge came with two outs and Hunter Pence on first base after drawing a walk from Rodriguez. Joe Panik hit a ground ball to second baseman Rickie Weeks, but with Pence advancing from first to second, Weeks was unable to charge the ball and had to wait for it to reach him, resulting in a close play at first.
The offense and the bullpen lifted up a strong effort from rookie right-hander Jimmy Nelson, who earned his third straight quality start. Nelson sailed through six of his seven innings, but he paid for his one big mistake, a three-run home run by Pablo Sandoval that tied the game at 3 in the sixth.
The home run was rendered moot by Parra's blast, and Nelson happily walked away with a win in a start where he felt he made progress.
"My delivery was much more consistent. I didn't have as many misfires out of the zone," Nelson said. "I made a lot more quality pitches and got ahead of a lot more hitters. That's why even with the three-run homer, I was able to throw seven innings. [Parra] picked me up right there. That was a huge hit by him. There were great plays behind me and that's what helped keep my pitch count down."
Before Parra's heroics, it was Carlos Gomez sparking the offense. Heading into Tuesday's game, the center fielder had had only three hits in his last 32 at-bats with 14 strikeouts. But he showed off his range of abilities, belting a two-run home run in the third inning and driving in Weeks with a two-out bunt single in the fifth.
"That was from 'Gomey.' That's an outstanding play," Roenicke said. "That's a guy looking at the game, at what needs to be done and knew that one run was more important than him maybe driving a ball into the gap. We wanted to get the run and 'Gomey,' he pulls the ball so well it's hard to play him in at third base. It was great timing and great execution."