The baseball superstar played a starring role in a now-viral moment, helping Jake Portella -- a senior at Haddonfield Memorial High School -- carry out a "promposal" for the ages.
"Will you go to prom with him?" asked Harper while standing with Portella at Giulia Leonetti's door.
And it didn't take long for her to say "yes."
"I don't think people understand the gravity of Bryce Harper standing in front of me and what that means to me specifically," said Leonetti, who is a Phillies superfan. "Immediate tears as soon as I saw Bryce. I just love him so much."
After the ask and still in shock, Leonetti went in for a hug -- but it was to Harper, not to her date Portella.
"I just said like, 'Can I have a hug?' I couldn't let him go. I had to make sure he was real," said Leonetti. "But as soon I snapped back, I was like, 'I need to hug Jake."
But how did Portella pull this off? The answer is simpler than you think -- Harper lives in the area.
Portella said the Phillies star first offered to send a recorded video via email, but then said he would do it in person.
"As I was leaving, he was like, 'What if we just do it right now?' And I couldn't turn that down," recalled Portella.
"I was just scared she wasn't going to answer the door because it was so spontaneous," he added. "I didn't really have time to make sure she was ready for this, or if she was even home."
But thankfully, Leonetti was there and all the pieces came together perfectly for a moment, neither of these high school seniors will ever forget.