Phillies pitcher Zack Wheeler said Bryce Harper told him recently that he “was about to turn it on.”

“And he did,” Wheeler said. “That was pretty cool.”

But when did Harper say that?

“We’ll keep that between us,” he said.

Well, it could have been before Harper hit his 100th career home run at Nationals Park on Monday in the first inning of a 7-4 win over Washington to start a crucial nine-game road trip.

Or maybe it was after the All-Star break, as Harper’s slugging percentage is 200 points higher in the second half than it was in the first. Perhaps it came earlier this month before Harper carried the Phillies throughout August.

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No matter when they were said, Harper’s words have proved profound as he has turned it on and kept the Phillies in playoff contention while becoming one of the favorites to win the National League’s MVP award.

Going into Tuesday’s game, his major league-leading OPS (1.008) had spiked 67 points in August thanks to his 21 extra-base hits, 10 of which have been home runs. No player has more homers this month than Harper.

He was batting .338 with a .480 on-base percentage and .721 slugging percentage since the All-Star break after slashing .282/.378/.520 before it. According to FanGraphs, Harper has been worth 1.8 Wins Above Replacement this month, more than any other position player.

There is no denying that Harper has turned it on.

“He’s been incredible. What he’s done for this club has been absolutely incredible,” manager Joe Girardi said. “He has that ability all the time. That’s how good of a player he is. He’s one of those guys who you don’t necessarily go and get a soda or a hot dog when he comes up to hit. You stay in your chair, and you wait to see the at-bat. But he’s meant so much to us.”

Harper started Monday night for the 41st straight game, remaining a consistent presence in the lineup while the team tries to overcome the absence of Rhys Hoskins and the nagging injuries of J.T. Realmuto.

The only game Harper has not started in the second half was the nightcap of a doubleheader on the first day back after the All-Star break, meaning Harper has not yet had an actual day off in the second half.

“This is a time of year you have to really grind it out,” Girardi said. “We’ve had some strategic days off. But I know he’s being pushed. But he wants to be pushed. He wants to be great. He wants to help us make the playoffs. So that’s what he’s doing.”

Harper played in 97% of the games during his first two seasons with the Phillies, so it’s not surprising that he’s in the lineup so often. But it feels more appreciated this season after he missed time earlier this year with a sore back and the pieces around him seem to change constantly.

Harper said he learned during his time in Washington from Jayson Werth and Dusty Baker how to know when the time is right to rest. It’s been a while since he thought the time was right, and it might be hard for Harper to sit now as the Phillies enter September fighting for a playoff berth.

“I just have to keep going,” Harper said. “That’s what this organization expects. That’s what these fans expect as well. No matter who’s on the mound or how I’m feeling, I have to keep posting every day. I think this organization deserves that, my teammates deserve that, and the fans as well. No matter how I’m feeling or what I’m feeling that day, I want to play as much as I can.

“I’ve thought about taking days off. I’ve thought about many times going in there [and saying], ‘Hey, maybe I can get one today and it’ll do me good.’ But every time I get to the ballpark and think about it or telling Girardi, ‘Hey, I feel I need one,’ then I get to the ballpark and it’s ‘Never mind, I want to play.’ I want to keep going. I want to keep playing for my teammates, for Philadelphia and all the fans.”

The last time Harper led the majors in OPS, he won the MVP in 2015 when he was with the Nationals. And his August is putting him in that conversation again. Entering Tuesday, Harper ranked sixth in the National League in batting average (.302) and second in on-base percentage (.417) and slugging (.591). His main competition seems to be Fernando Tatis Jr., who is slashing .284/.364/.643 and trying to push the Padres to October. Atlanta’s Freddie Freeman (.296/.390/.508) and the Dodgers’ Max Muncy (.261/.390/.542) also have cases.

» READ MORE: Why the Phillies will miss Rhys Hoskins for more than just his power bat

“I just feel like we have a long way to go. We have another whole month to play,” Harper said. “You guys know, man. I talk about the whole season at the end. I just try to stay in the moment, stay in the game and not really worry about what’s behind me or what’s ahead. Kind of what we need to do as a team right now, kind of just stay where we’re at, be where we are and forget what’s behind us and look forward to tomorrow.”

Harper’s case for the MVP could be hard to beat if he produces in September the way he did in August. He has slashed .278/.393/.509 in his career during September and October. He proved this month how valuable he was to the Phillies, as he kept them within striking distance of both the National League East lead and the NL’s second wild card.

If he ends the season by lifting the Phillies back to the postseason, it could be hard to find someone more valuable. He just needs to keep it turned on.

“I’ve faced him so many times in my career and I’ve always enjoyed just watching him be a baseball player,” Wheeler said. “And now that I’m on his team and I’m playing with him and watching him every day, it’s pretty fun. It’s special. There’s not a lot of guys out there like that.”