PHILADELPHIA — Bryce Harper knows everyone in the dugout and ballpark expects him to get clutch hits in moments just like this.

Boy, he crushed it.

Harper blasted a grand slam with one out in the ninth inning, capping a six-run rally that sent the Philadelphia Phillies over the Chicago Cubs 7-5 Thursday night for a three-game sweep.

Harper delivered his biggest hit yet in his first season after signing a $330 million, 13-year contract with the Phillies, celebrating while running around the bases and then getting mobbed by teammates at the plate.

“Before I went to the plate, I touched my heart and I was thinking to myself: Why am I not jittery? Why am I not excited? But that’s just how I am,” Harper said. “I go up there and each at-bat is the same. I don’t think about bases loaded. I try to get a pitch I can drive and hopefully good things happen. I love those moments. I love those opportunities. I think it helped me a lot from a young age going through those emotions and having those opportunities at 8, 9, 10 years old in big-time games going to different states and cities playing for a lot of teams.”

“I just love it. It’s a lot of fun. These fans do expect that and I expect to do that for them on a nightly basis and if I don’t, they’ll let me know and I like that, too,” he said.

Cubs starter Yu Darvish struck out 10, silencing Philadelphia’s bats for seven innings a night after the Phillies scored 11 runs in former manager Charlie Manuel’s debut as hitting coach.

But the Phillies rallied against Chicago’s bullpen and moved within one game of the Cubs for the second wild-card spot in the NL.

Pinch-hitter Brad Miller chased Rowan Wick with an RBI single in the ninth that cut it to 5-2 and Roman Quinn greeted Pedro Strop with an RBI single to make it a two-run game. Strop (2-5) hit Rhys Hoskins to load the bases with one out.

Derek Holland entered to face Harper and got ahead 0-2 in the count. Harper fouled off a 2-2 pitch before launching his 25th homer way out to right.

“I think everyone who watches baseball expects him to do that every time he’s up,” Phillies starter Drew Smyly said. “He’s fun to watch.”

Harper has seven homers and 15 RBIs in the last 12 games.