ST. LOUIS — Gregory Polanco helped the Pittsburgh Pirates serve up a nice slice of victory pie.

Polanco went the opposite way for a three-run homer and John Jaso added a two-run drive, leading Gerrit Cole and the Pirates over the St. Louis Cardinals 10-5 Sunday.

Facing reliever Matt Bowman, Polanco capped a four-run seventh inning by slicing his homer barely over the wall in left field, just inside the foul pole.

“I was looking for a good pitch. He threw me one that was out and over the plate and it was something I could drive,” Polanco said. “Whenever you hit the ball to the opposite field, it’s good. I stayed with the pitch and hit it that way.”

“I was a little surprised it went out. I was more worried about it staying fair,” he said.

Cole (3-3) gave up two runs and six hits in six innings. He struck out seven and walked two.

“He stayed aggressive and used all his pitches,” Pirates manager Clint Hurdle said. “I felt it was a really good bounce-back start from his last start. As the game went along, he got stronger.”

Mark Melancon relieved with the bases loaded in the ninth and got Yadier Molina to ground into a game-ending double play for his ninth save.

The Pirates took two of three at Busch Stadium and have won five of six from St. Louis this season.

“It’s always going to be a spirited series,” Hurdle said. “They play hard, they’re well-coached and they play to the finish. The way I look at it, we were a bad-bounce ground-rule double away from a sweep. It’s hard work to come in here and win, but we did it.”

Michael Wacha (2-3) lost his third consecutive decision for only the second time in his career, the first coming in 2014. He allowed four runs on six hits and two walks in six innings.

“I thought he was good,” St. Louis manager Mike Matheny said. “I thought his stuff looked very good. They were grinding out some of their at-bats.”

In his last three starts against the Pirates, Wacha has given up 15 runs and 20 hits in 14 1/3 innings.

Pittsburgh scored three times in the fifth for a 3-1 lead. After a one-out walk, Chris Stewart hit an RBI double.

“The one-out walk in the fifth got things going and it kind of snowballed,” Matheny said.

After fouling off several pitches, Jaso homered just over the wall in right field with two outs.

“He has a plan. He’s a very quiet guy but he’s a very cerebral guy,” Hurdle said. “He always goes up there with a plan. He’ll (swing) early, have extended at-bats.”

Wacha said Jaso hung tough in the at-bat that ended with the homer.

“I left a mistake changeup in the top of the zone and he didn’t miss,” Wacha said. “He put together a great at-bat.”

The Pirates added a run in the sixth when former Cardinals star David Freese hit an RBI single. He drove in Starling Marte, who doubled twice and singled.

Jaso, who had three hits, doubled home a run in the seventh against Bowman. Polanco added his homer for an 8-2 lead.

Rookie Jeremy Hazelbaker hit his sixth homer for St. Louis. Stephen Piscotty added four hits.