Southern California has fired defensive coordinator Alex Grinch, less than 24 hours after another disastrous performance in a loss to Washington.

USC announced defensive line coach Shaun Nua and associate head coach/inside linebackers coach Brian Odom take over the defensive unit for the rest of the season.

"USC Head Football Coach Lincoln Riley announced today that Defensive Coordinator Alex Grinch has been relieved of his duties," the athletic department said in a statement. "Defensive Line Coach Shaun Nua and Inside Linebackers Coach/Associate Head Coach for Defense Brian Odom will serve as interim co-defensive coordinators for the remainder of the season. Additionally, Defensive Analyst Taylor Mays has been elevated to an on-field assistant coach and will work with the safeties."

USC's defensive woes

Grinch came to USC when Riley was hired after the 2021 season, but the defensive coordinator's firing has long been desired by the Trojans fan base, and even former USC players.

On Saturday, USC gave up 52 points in a loss to the Huskies, including giving up 313 rushing yards to a team that ranked in the bottom half of FBS in running the ball. The 572 yards given up was the most allowed since Riley became coach.

Despite the Trojans having a premier offense and reigning Heisman Trophy winner Caleb Williams, the defense has been blamed for a majority of the teams shortcomings in the two seasons under Lincoln Riley. The Trojans went 11-1 in the regular season in 2022, needing a win in the Pac-12 championship game to reach the College Football Playoff. Instead, USC gave up 47 points in a loss to Utah, and followed it up with a stunning loss in the Cotton Bowl against Tulane in a 46-45 defeat.

Things haven't improved this season. Despite having the second-best scoring offense in FBS at 45.5 points per game, USC ranks 119th in total defense by allowing 436 yards a game, and the 34.5 points allowed per game ranks 121st out of 130 teams.

The Trojans entered the season with national championship aspirations, and after a 6-0 start to the season that saw the Trojans rise as high as fifth in the US LBM Coaches Poll, USC has lost three of its last four games and is now unranked. The one win coming in a nail-biting 50-49 against Cal that came after the Golden Bears failed on a two-point conversion in the final minute of the game.

In the three losses this season, USC has given up 44.6 points per game, and has given up at least 40 points in five of its last six games. At 7-3 with a 5-2 conference record, the Trojans are virtually out of the conference title race and a New Year's Six bowl appearance. The three regular season losses is also the most in Riley's seven-year head coaching career.

The Trojans have two games left on the regular season: on the road against Oregon, who have the top scoring offense in FBS, and the crosstown rivalry game at home against UCLA.