PITTSBURGH — Zack Wheeler pitched seven sparkling innings, and Bryce Harper hit a home run off ace Paul Skenes on Sunday to lead the Philadelphia Phillies to a 6-0 win over the Pittsburgh Pirates and a sweep of the three-game series.

The resurgent Phillies improved to 15-4 since interim manager Don Mattingly took over, and they snuck over the .500 mark (at 24-23) for the first time since April 7. Philadelphia has not lost a series with Mattingly at the helm, and the club even went 1-0 without him. On Saturday, in another 6-0 win over the Pirates, Dusty Wathan was acting manager while Mattingly attended his son Trevor’s graduation from Purdue University.

“I thought we battled,” Mattingly said of how the Phillies hit Skenes, the defending National League Cy Young Award winner. “I thought we just fought him. And that’s what you have to do against guys like him. He’s going to get his outs; he’s going to make pitches. But you’ve got to keep fighting and just keep fouling off, trying to fight just to get something. And I thought we did that kind of up and down the order.”

Wheeler (3-0) gave up four hits while striking out eight and walking one. His ERA is 1.99 in six starts since beginning the season on the injured list while recovering from surgery to have a blood clot removed from his upper right arm. Jonathan Bowlan and Tanner Banks pitched one inning each to finish the five-hitter.

“We feel good,” Phillies shortstop Trea Turner said. “This is what we’re capable of; we obviously didn’t want to start the way we did, but we feel good, we feel like we’re playing good baseball.”

Harper led off the sixth inning with his 12th home run to push the Phillies’ lead to 3-0. Later in the inning, Bryson Stott added a two-run double off reliever Isaac Mattson with the runs being charged to Skenes (6-3), who was lifted after Alec Bohm singled and Brandon Marsh doubled.

The Phillies have won seven of eight games, though they are eight games behind the first-place Atlanta Braves in the National League East. The Phillies were 8-18 on April 25 when they activated Wheeler and are 16-5 since his return.

“Just focus on who is front of us,” Turner said with regard to getting back into playoff contention. “There’s a lot of baseball left. We’ve got to keep playing good team ball and stack up wins.”

Skenes tied a career high by giving up five runs in five-plus innings. He allowed six hits, struck out seven and walked one.

Skenes’ career-best scoreless innings streak ended at 20 when the Phillies had a two-run fifth. Justin Crawford drove in the first run on a groundout, and Turner followed with an RBI single as the Pirates lost for the fourth time in five games.

The Associated Press contributed to this report.