But it wasn't long that he started to hear about past guys.
Darrell Griffith, who was nicknamed Dr. Dunkenstein, Pervis Ellison, Alvin Sims, Cornelius Holden and plenty of others just to name a few.
"I didn't know about all of that," Harrell said.
The sophomore from Tarboro, N.C., soon found out and when he started dunking all over the competition he started hearing about the record book.
On Tuesday night, Harrell took his place atop the single-season dunk record list with four dunks to give him 63 for the season. He passed the old mark of 59 set by Ellison and Chane Behanan.
"It's nice because it's a record I get to hold," Harrell said. "When I went into it, I wasn't too focused on it but people started talking about it.
"There's been a lot of great guys here, so to hold it is a great honor. Now, the only thing that matters is how high I can take it."
Harrell has 107 dunks in two years and is currently sixth all-time in dunks at U of L with Chane Behanan the next player he will pass on the list.
Pitino called Harrell being in the dunk record book "incredible."
" I would think right away that Dr. Dunkenstein would have had that by many dunks," Pitino said, referring to Griffith.
But he doesn't. Harrell is the single-season king and now he has a new goal to put some distance between his record and the old mark.
"I think I can bump it up to 100 before the end of the year," Harrell said with a smile. "I'm going to try and get it as high as I can."