Alex Grinch was one of the first people on Lincoln Riley's private plane to Los Angeles. They had visions of building a college football powerhouse together. Less than two years later, the embattled defensive coordinator is out.

After weeks of unwavering support for Grinch, Riley reversed course by firing the coordinator Sunday, less than 24 hours after USC's 52-42 loss to Washington at the Coliseum. The decision with two regular-season games remaining came as Riley held onto hope that the Trojans (7-3, 5-2 Pac-12) can salvage their season and redirect the future of a program that feels like it's just a serviceable defense away from a College Football Playoff breakthrough.

"I have complete belief and conviction we will play great defense here," Riley said Monday. "It is going to happen. There's not a reason in the world why it can't. We'll continue to take the steps we have to do to do it and we're going to be very aggressive that way."

Reviewing the tape of the loss — USC's second consecutive home loss and third in the last four weeks — on Saturday night, Riley started considering the decision to fire his close friend who was one of his first hires when he left Oklahoma. Washington's 572 yards were the most allowed by USC since 609 against UCLA in 2021. Washington running back Dillon Johnson, whose previous rushing career high was 100 yards, rushed for 265. The Trojans had given up more than 34 points for a sixth consecutive game.

It was a sleepless night, Riley said. He considered it more Sunday morning.

"The bottom line is it didn't get to where he, I, any of our players, any of us expected," Riley said, "and we all take ownership in that."

Riley fired Grinch with games against No. 6 Oregon and rival UCLA remaining and the early-signing period creeping up on Dec. 20. The looming deadline will lurk in Riley's mind as he begins a search for Grinch's replacement, but it will not rush the decision.

"Nothing will trump getting the right person in here," Riley said, "because we're gonna play great defense here. Like, period. It's gonna happen. It's gonna happen soon."

Riley said he has thought about factors he'll consider in the hiring process but didn't divulge specifics. He plans to spend "99%" of his time during the next two weeks coaching the team through the remaining games. Part of the decision to make the change at this point of the season was because "we still have a lot to play for," Riley said.

The Trojans could still have a path to the Pac-12 championship game if they win both of their remaining games and get help from other teams with two conference losses such as Oregon State, Utah and Arizona.

Defensive line coach Shaun Nua and linebackers coach Brian Odom were elevated to co-defensive coordinator roles while defensive analyst Taylor Mays will work as an assistant coach for the safeties. The coaches have a plan for how to split up play-calling duties, although Riley did not divulge specifics.

The late-season adjustments could feel like too little, too late for a defense that has been spiraling for weeks. The Trojans are allowing 34.5 points per game, on pace to be the school's worst scoring defense since at least 1955, when records are first available. The current mark for futility is 31.8 points allowed in 2021, the final year of the Clay Helton era.

Since taking over for Helton, Riley has rebuilt USC's image and playoff hopes with the same high-scoring offense he used to make his mark at Oklahoma, but familiar defensive disappointments also traveled from Norman.

Despite helping the Sooners to two playoff appearances in three years with Riley at Oklahoma, Grinch's defenses never ranked better than 29th nationally in total or scoring defense.

Getting his first coordinator position under Riley's coaching mentor Mike Leach at Washington State, Grinch's best defenses were built on stopping the run, creating chaos in the backfield and forcing turnovers. The Trojans missed almost every mark this season.

USC's 4.84 yards allowed per carry is the worst in the Pac-12.

This story originally appeared in Los Angeles Times.

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