Mathis, a freshman from Oak Park, Michigan, had the surgery at Piedmont Hospital in Athens, Georgia, where he was being kept in ICU as a precaution.
His father, Terence Mathis, told DawgNation that his son had been suffering from headaches and severe sinus pain.
"I want everyone to know my son is OK and will be back better than ever because of Coach [Kirby] Smart and the University of Georgia medical staff and coaching staff," Terence Mathis told DawgNation on Thursday night. "The procedure [on Thursday] was a success, and I want to thank Coach Smart and Georgia for the way they treated my son and my family through all of this. Coach [James] Coley is at the hospital with my son right now, in fact."
Mathis, the No. 14 dual-threat quarterback prospect in the 2019 ESPN 300, worked as the Bulldogs' third-string quarterback this spring behind returning starter Jake Fromm and junior college transfer Stetson Bennett. Mathis flipped from Ohio State to Georgia on national signing day, after former Bulldogs player Justin Fields transferred to play for the Buckeyes.
Smart couldn't be reached for comment on Friday morning.
It wasn't immediately clear when Mathis will be able to return to workouts or what his status will be for the upcoming season. The Bulldogs open the 2019 season at Vanderbilt on Aug. 31.