Nittany Lion offensive coordinator John Donovan and the cornerback from Sayerville High in Parlin, N.J., converse daily on social media, Hartsfield said. Those interactions, along with the occasional phone call, led Hartsfield to believe an offer might be forthcoming when he took an unofficial visit to University Park Saturday.
His gut instinct was right.
"It meant a lot," Hartsfield said of the PSU offer, his sixth. "It was just amazing. [Donovan] said I'm a very athletic kid that could play either side of the ball. [Head] Coach [James] Franklin said he would start me off on defense, at safety or corner, and use me as kick or punt returner to use my athleticism."
Hartsfield did plenty for the 8-3 Bombers in 2013, but his biggest impact came on defense. There, he made 44 stops, picked off four passes and deflected seven more.
Being recruited as a defender at Penn State was new, the junior said. On a previous stop at PSU, for its February Junior Day, the staff was looking at him as a running back.
"I was watching a lot of the running backs at [Saturday's spring] practice because of that," Hartsfield said. "I got to watch some of the safeties, though, and they have really good safeties at Penn State, and really good corners.
"Their coaching defensive backs group is really good, too."
A position switch wasn't the only difference for the 6-foot, 185-pound three-star Saturday. His parents came along on this trip, and were able to gauge the differences Franklin's staff has from Bill O'Brien's, which left in January.
"I got to see a lot during Junior Day, but I didn't get to go with my parents," Hartsfield said. "It's a really good thing to look at a college with my parents. They came to the Illinois game [in 2013] but they didn't like the whole thing in total. It didn't have a good vibe.
"I came to Junior Day and told them the new staff is great and that they're coming together and that they would really like it. They came up and had a really good time. We saw the education building, locker room and got a little tour."
Hartsfield and his family also gave high marks to the Lions' practice.
"I really like the way they run practice," he said. "It's very intense. They really don't stand around; they're always moving and there are not a lot of breaks.
"To see Coach Franklin running around, he's not like a coach who stands on the sideline. He's teaching kids technique, and that's really a plus to see the head coach doing that and not just assistants."
Though he has yet to announce a top five, Hartsfield said Penn State will be in it once he does. The junior plans to visit Wake Forrest next weekend before wrapping up visits for a bit.