Afterward, he pronounced his two-year career with the Nittany Lions as officially behind him and declined to answer questions about anything related to Penn State.
"My relationship with Penn State and everything was a great experience," Redd said. "They gave me some excellent opportunities. But I'm opening a new chapter of my life.
"I'm a Trojan now."
A 5-10, 200-pound junior who is eligible to play right away due to NCAA sanctions issued to Penn State, Redd split carries at running back with incumbent USC starter Curtis McNeal and appeared speedy and shifty. He ran hard and broke a few deep runs in team-wide drills.
"It's only Day 1," Redd said. "Getting used to the lingo is the hardest thing right now, but I did pretty well today."
He also said USC's practices appeared a "little more laid back" than Penn State's so far.
"You really can be comfortable playing ball," he said.
McNeal, a senior, was slated to be the Trojans' clear-cut No. 1 running back until Redd was recruited. He's still the likely starter but will now face stiffer than expected competition.
"We're all out here competing for that No. 1 spot," Redd said of McNeal and the other USC running backs. "They understand that and I understand that. There's no animosity or hard feelings."
Redd, a Connecticut native, did make one minor slip-up when speaking with the media after practice, referring to the Trojans' opening-day opponent as Ohio before correcting himself later on.
Penn State plays Ohio in its season opener, on Sept. 1. USC plays Hawaii the same day.
Pedro Moura covers USC for ESPNLosAngeles.com.