PITTSBURGH — The Pittsburgh Pirates have just one off day in September and it comes in advance of a pivotal series, but it figures to be an enjoyable one.

Josh Harrison hit a winning single in the 11th inning, and the Pirates rallied from a five-run deficit to beat the Milwaukee Brewers 7-6 Sunday and remain 2½ games behind St. Louis in the NL Central race.

With the score 6-6, pinch-hitter Travis Ishikawa singled off Tyler Thornburg (0-1) and advanced when left fielder Shane Peterson bobbled the ball for an error. Pinch-runner Pedro Florimon moved to third on Jordy Mercer’s groundout, and Sean Rodriguez was hit by a pitch.

After a wild pitch advanced Rodriguez, Harrison lined a single to left. Harrison was playing because Starling Marte had a stomach flu.

Pittsburgh opened a four-game margin for the NL wild-card lead over the Chicago Cubs, who start a four-game series at the Pirates on Tuesday.

“We’ll enjoy this win tonight then take (Monday) off, regroup, relax, watch some football then get ready for two on Tuesday,” Harrison said with a smile. “It should be fun.”

Harrison made sure the Pirates had fun at the end of a long day Sunday with the fifth game-ending hit of his five-year career.

“Josh, he does a lot of things to help us win games,” Pittsburgh manager Clint Hurdle said. “He brings energy, edge and attitude.”

Harrison, Andrew McCutchen and Jung Ho Kang had two hits apiece for the Pirates, and Pedro Alvarez hit his team-leading 23rd home run. Harrison went 8 for 19 as Pittsburgh won three of four in the series.

Jared Hughes (3-1) induced Scooter Gennett to hit into an inning-ending double play in the 11th after the Brewers put runners at the corners.

“You could make a case that we should have played the infield, especially with a fast runner up to bat,” said second baseman Neil Walker, the pivot man on the double play. “But that shows the faith (Hurdle) has in Jared and our defense, and we were able to get out of it.”