The jab drew a flag from the referee and resulted in a flagrant foul against the 6-foot-5, 270 pound Williams. He was ejected from the game and escorted by a USC staff member off the field and into the locker room in the second quarter, where he remained for the rest of the game.
Coach Lane Kiffin said Pac-12 policy would have allowed Williams to rejoin the team on the sideline for the second half, but the coach elected to have Williams stay in the locker room.
"We were pulling him out regardless of if the refs did it," Kiffin said after practice on Wednesday. "I think that (he) learned a lesson."
"It kind of sucked not being able to be out there with my team," Williams told reporters following Wednesday's practice. "I just took care of everything I needed to do and I just made a promise to myself that I won't be in that situation again."
USC announced Tuesday evening the Pac-12 will not be taking any further disciplinary actions against Williams, leaving him eligible to play on Saturday at Arizona.
"I'm really relieved," Williams said of his eligibility remaining intact. "I talked to all of the coaches and they got everything taken care of and so far I'm just ready to play."
"It was a learning moment for a true freshman," Kiffin said. "I know he understands that and I can't imagine it ever happening again."