PHILADELPHIA -- Bryce Harper wanted Keith Maguire Jr.’s hat.

Yeah, Maguire couldn’t believe it, either.

Maguire is a 21-year-old from Media, Pa., who graduated from Malvern Prep. He is a lifelong Phillies fan, too. As an 8-year-old, he stood on his seat at Citizens Bank Park for four innings to watch the second half of Game 5 of the 2008 World Series with his father. He attended the championship parade a couple days later.

On Thursday, he exchanged hats with Harper.

“What the heck just happened?” Maguire said. “It was so random. It was awesome.”

Maguire almost turned down the opportunity to attend the Phillies’ series finale Thursday afternoon against the Padres with his buddies Gavin McHugh, Mike Hussey and Mike O’Brien. Maguire plays linebacker for the Clemson University football team, and he is headed back to school on Sunday.

But he figured it could be fun, so he went.

“I realized this morning I had no Phillies stuff with me, it’s all at school,” Maguire said. “I said I’ll just buy something when I get to the game. … I saw this nice hat sitting up on the rack right next to the register, so I said I might as well.”

Maguire took his seat just next to the Phillies’ dugout. A few innings into the game, the four buddies got Harper’s attention. The Phillies’ star slugger waved at them.

Pretty cool, Maguire thought.

But then Harper got their attention. He was waving his maroon Phillies cap at them.

“Yo, Keith!” McHugh said. “Keith! They want you.”

Maguire stood up. He looked into the Phillies’ dugout.

“Bryce wants your hat,” McHugh said.

“Who?”

He saw Harper waving his cap at him. Maguire took the cap off his head and tossed it to McHugh. Maguire said he did not realize that Harper wanted to make a trade. He just thought it was cool that the NL MVP wanted his cap, so he figured he could have it.

But after McHugh tossed Maguire’s cap to Harper, Harper tossed his signed cap to Maguire.

Maguire had no idea it was signed until he had it.

“Just really liked the hat, so I signed mine and asked if he wanted to trade,” said Harper, who has been sidelined since Sunday because of an injection in his injured right elbow. “He was really cool about it and made it happen. Always fun interacting with the fans here at home.”

About a minute after he got it, Maguire pulled out his phone to snap a picture. At that moment, he got a video from his cousin, telling him that he got some face time on TV. But the video would not load, so Maguire had no idea how much face time he meant.

“I think they showed us on TV,” Maguire told his buddies.

Then everybody’s phone blew up.

“I’m getting videos, I’m getting texts, I’m getting tweets, I can’t get anything to load,” Maguire said. “All these things in a matter of three minutes. By the time the seventh inning rolled around, it was full blown all over the place. I know a bunch of kids on the Clemson baseball team. They texted me. ‘No way, this is crazy. I’ve got to see this when you come back.’ It was all over the place.”

Maguire promises to keep the hat safe. It’s not like he can wear it, anyway. Harper wears a size 7-1/4 cap. Maguire wears a 7-1/2.

“It’s enough for me to just rest it on my head, to let people know that it happened,” Maguire said. “But that will be going on the shelf, and it will be sitting there for good. I wouldn’t even wear it, anyway. It’s a pretty cool piece of memorabilia right there. It was a great day.”