Kingsbury is the first high-profile assistant hire since USC announced Clay Helton would remain as head coach.
Three of the four assistants were fired and quarterbacks coach Bryan Ellis left.
The Trojans finished the 2018 season 5-7 – the worst program record since 2000 – and USC finished bowl ineligible for the first time since NCAA bowl restrictions in 2011.
With a losing record in sight and Helton’s job on the table, USC allowed 24 unanswered points to No. 3 Notre Dame in a 24-17 defeat at the Coliseum on Saturday.
With rumors swirling around head coach Clay Helton's job security, follow along as USC takes on undefeated Notre Dame in a game it must win to become bowl-eligible.
In its final game of the regular season, USC looks to defy the odds and earn a bowl game appearance by beating Notre Dame.
The loss drops USC to 5-6 on the season and marks the end of a three-year winning streak over the Bruins, almost certainly eliminating the Trojans from bowl eligibility.
USC takes on UCLA in a crosstown matchup in hopes to earn bowl eligibility.
USC will face UCLA at the Rose Bowl on Saturday to close conference play.
Cornerback Iman Marshall apologized for his actions against Cal at practice.