The Brewers rocked Archer (4-7) for six runs and six hits in the third, when two close calls in the outfield started the trouble for Pittsburgh.
"I didn't execute," Archer said. "Five consecutive hits. I didn't throw the ball where I wanted to, and they capitalized on every single one. One or two mistakes, that's OK. A six-run inning is inexcusable."
A pair of fine defensive efforts by the Pirates came up short and set the stage for the Brewers' big inning.
Right fielder Gregory Polanco had the ball pop out of his glove on a long sacrifice fly by Jesus Aguilar. Center fielder Starling Marte raced and dove for Travis Shaw's sinking liner, but the ball trickled free for a double. Ryan Braun followed with an RBI single.
"There are tipping points in the game every day," Pirates manager Clint Hurdle said. "Those were a couple of them, for sure."
Still, he praised the defensive effort.
"The one that cracked my heart a little bit was Marte laying out in center field, catching the ball, but it rolled out of his glove," Hurdle said. "He gave his best effort. It was everything you want to see from a guy who's won a Gold Glove."
Even Brewers manager Craig Counsell tipped his cap to Marte.
"He made a great attempt to make a great play," Counsell said. "Travis hit a ball hard, and Marte made a great effort."
Schoop hit a solo shot in the seventh off Nick Kingham, recalled Saturday from Triple-A Indianapolis.
Adam Frazier, who hit a three-run homer in the Pirates' 9-1 win Saturday night, teed off on Anderson for a two-run shot and Polanco followed with a solo drive that pulled the Pirates to 6-4. A single by Francisco Cervelli chased Anderson with nobody out and brought on Josh Hader.
Corey Dickerson grounded to second baseman Schoop, who tossed to shortstop Orlando Arcia at second. Cervelli slid into Arcia as he made the relay throw to first. Second base umpire D.J. Reyburn called Cervelli out for interference and gave the Brewers a double play. Elias Diaz grounded out to end the inning.
Hader followed up with a 1-2-3 seventh, and Joakim Soria worked around two infield throwing errors in the eighth. Jeremy Jeffress, who blew a save Friday night, pitched the ninth for his seventh save.
Archer, who exited his previous start against Atlanta after four innings with left leg discomfort, walked two and struck out five in his second career start against Milwaukee. His first, a 2-1 victory, came as a member of the Tampa Bay Rays last August.
Pirates: INF Josh Harrison wasn't going to play in a precautionary move, but he did pinch-hit in the fifth. He's been dealing with a left hamstring issue and left Saturday night's game in the eighth after hustling from first on a double by Kevin Newman. "Everything was fine up to that point," Harrison said. Asked if a trip to the disabled list was possible, he said: "I don't plan on it."
Brewers: In the seventh, Pirates reliever Kyle Crick hit Shaw with a pitch just above the right knee. After a brief delay, Shaw trotted down to first. He had a huge red mark on his thigh after the game, but said he'd be ready to go Tuesday.
IT'S A FIRST
The victory gave the Brewers their first series win against Pittsburgh this season. Milwaukee improved to 4-9 vs. the Pirates overall with two three-game series remaining between the NL Central rivals
NO COMPLAINT FROM HURDLE
Cervelli aimed for Arcia instead of the bag while trying to break up the double play. After a slight delay, Reyburn signaled Cervelli out for interference.
"It's a book rule," Hurdle said. "If he doesn't call it, they're going to review it and get the call in New York. You have to make an attempt to get to the bag. It's a rule. Unfortunately, we didn't make an attempt to get to the bag on the slide."
Frazier is batting .354 (29 for 82) with 11 doubles, four homers, 17 RBI and a 1.034 OPS in 26 games since being recalled on July 25. His seventh home run of the season was his fourth in seven games against the Brewers dating to last September. During that span, he's batting .429 (12 for 28) with 12 RBI vs. Milwaukee.
Brewers: RHP Junior Guerra (6-8, 3.72) makes his fourth start this season against Cincinnati on Tuesday as the Brewers begin a six-game road trip.
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