Pirates starter Charlie Morton did not have his best stuff Wednesday night. But he did what he does best: get ground balls.

Morton induced groundout after groundout in a strong outing to lead the Pirates to a 4-2 victory against the Miami Marlins at PNC Park.

He allowed two earned runs on six hits in seven innings striking out five batters without issuing a walk. He retired the final 11 batters he faced on the night.

Of the 21 outs the sinkerballer recorded 14 were the result of a ground ball.

"I just worked the sinker down to both sides of the plate" said Morton who rebounded from a pair of rough outings to pick up his fourth win of the year.

Ground balls account for 64.7 percent of all balls hit in play against Morton this season the highest percentage of his career. Morton said he has been using his sinker more often this season -- more than 70 percent of the pitches he has thrown.

"I feel like a lot of them have been finding holes so I don't know how to take that" he said. "But I do feel like I'm getting a lot of ground balls with my sinker."

The sinker has even more late life on it this year manager Clint Hurdle has noticed and the late movement has led to a career-high strikeout rate for the right-handed pitcher.

Hurdle said the rest Morton got this offseason after undergoing Tommy John surgery in June 2012 has added more velocity and more movement to Morton's pitches.

But Morton said the surgery also has forced him to struggle at times to perfect his delivery which has led to a handful of rough outings.

"I am coming off a major arm surgery and that's just the reality of it" he said. "I'm going to have misfires and you'll see those. I'm running balls way in on lefties casting balls on righties and misfiring occasionally. It's strange because I'm not walking a lot of guys but there are those pitches that are like 'Whoa where did that come from?'"

The Pirates charged ahead of the Marlins in the fifth inning behind a pair of wild pitches from Marlins starter Tom Koehler.

With runners on first and second Koehler threw a pitch that bounced off the dirt glanced off catcher Rob Brantly's glove and rolled toward the Marlins dugout allowing Josh Harrison to advance to third and Jordy Mercer to move to second. It also let Morton swing freely at the plate and he slapped a single into right field on the next pitch scoring Harrison to tie the score 2-2.

It was Morton's second hit of the season and his first RBI since 2011.

"When you get breaks you need to move on them" Hurdle said. "We've been able to do that. ??? We've been on the other end of that. One of the signs of a good team is when you get an opportunity you move upon it. And we were able to move upon it."