PHILADELPHIA -- Kyle Gibson couldn’t have done much more to endear himself to the Citizens Bank Park crowd than he did Friday night.

He helped vault the Phillies into first place.

Making his home debut and second start overall since being acquired at last week’s Trade Deadline, Gibson pitched his new club past the division-leading Mets, the 4-2 victory flipping the standings at the top of the National League East and extending the Phils' winning streak to six games.

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“I think I can get used to all these big moments and big spots being really meaningful and a lot on the line,” Gibson said. “That's just so much fun.”

Gibson held the Mets to one run over six innings, also delivering a go-ahead hit with his fifth-inning RBI single against Marcus Stroman. It was the first RBI of Gibson’s career, though he tried to temper his excitement after arriving safely at first base.

“I think I can act like I’m playing it cool,” Gibson said. “But inside, I'm a little kid.”

“He got to 2-0, I was like, ‘He’s got to be taking right here,’” Bryce Harper said, “Then, bam, base knock; me and J.T. [Realmuto] looked at each other like, ‘All right, well, there we go.’”

There was no hiding Gibson’s elation in the preceding innings, as he escaped a couple of big spots with the game tied 1-1. First, he got out of a bases-loaded, no-out jam in the fourth, inducing a Brandon Nimmo double play that ended the threat and resulted in an animated fist pump by Gibson.

“When he pitches, it's an art; it's not just, ‘Throw it as hard as I can, go as long as I can,’” Phillies manager Joe Girardi said. “He got a ton of ground balls for us tonight, and that's what he's capable of doing.”

An inning later, the right-hander worked around a leadoff double by Jeff McNeil, striking out Javier Báez to post another zero as the crowd of 30,106 brought a playoff-like atmosphere.

“Overall, I'm a fairly even-keeled guy, but that overflow of emotion just kind of happens in some of those big situations,” Gibson said. “I don't know that I really could imagine what this atmosphere would look like. It’s met or exceeded every one of my expectations and the excitement I had coming here.”

Gibson turned the 2-1 lead over to the bullpen after six innings, then held his breath when Alec Bohm’s second error of the night put the tying run on base with two outs against Héctor Neris in the seventh.

But Pete Alonso hit a slow roller to second base, where Jean Segura made a spectacular play to end the inning, causing both Neris and Segura to emulate Gibson’s earlier fist-pump routine.

“I love it,” Girardi said. “Emotion is important in this game as long as you're not showing people up. I didn't feel like our guys did any of that.”

With nervous energy flowing throughout the ballpark, Harper -- who received a number of “MVP!” chants during his at-bats -- allowed the crowd to exhale and explode, continuing his recent offensive onslaught with a monster two-run blast off Edwin Díaz in the eighth.

“Big spot, big moment,” Harper said. “Ended up being a big homer as well going into the ninth.”

“It just gives you a little breathing room,” Girardi said. “In today's game, one through nine can hit the ball out of the ballpark. One mistake ties the game up, so that's a huge moment.”

It turned out to be crucial after Ian Kennedy, who was part of the same deal that sent Gibson to Philly from Texas, gave up a solo homer to Jonathan Villar before closing out the game for his first save with the Phillies.

The Mets had been in first place every day since May 9, but that is no longer the case. There are still nearly two months to go in the regular season, but when the Phillies wake up on Saturday, they will be looking down at the rest of the NL East for the first time in three months.

“It’s better than the alternative,” Girardi said. “It's just a great atmosphere tonight. We want to continue to build off of this, but this is a big win for us.”