By the final weeks of UCLA's 1980 season, Terry Donahue was well aware of the whispers about his future. The Bruins coach had yet to beat USC in his tenure, losing four times in four tries, and in the crosstown rivalry, that just wasn't cutting it. His fifth attempt, Donahue figured, would be a referendum on his place as UCLA's coach.

"The word on the street was if I didn't win the game, I was out," the longtime Bruins coach told The Times in 2011.

Donahue, who died in 2021, never had to find out if the rumors were true. He beat the Trojans in 1980, kept his job and went to become the winningest coach in Bruins history. His successors at UCLA wouldn't be quite so fortunate.

Ever since Donahue's day, the crosstown rivalry has been littered with referendums gone awry for Bruin coaches. In 2007, Karl Dorrell lost his job two days after losing to the Trojans. Rick Neuheisel was fired after a 50-0 flogging by USC in 2011. And Jim Mora was ousted in 2017 on his birthday, one day after a third straight loss to the Trojans, who seemed to revel in delivering the final blow to one Bruin coach after another.

The word around Westwood this rivalry week suggests the same fate could befall UCLA's Chip Kelly if the Bruins are humiliated at the Coliseum in the wake of back-to-back losses to Arizona and Arizona State. Nearing the end of his sixth season, Kelly could be coaching for his job Saturday. Though, the more pertinent question may be whether a win over the Trojans, whose season is also unraveling, would even be much of a referendum at all.

Like his predecessors, Kelly understands the importance of winning the rivalry game. Donahue provided a primer, Kelly said, the coach tearing up at the memory of the legendary Bruin who was recently honored with the unveiling of a statue at the Rose Bowl.

"The first time I met with him he's like, 'You gotta beat your rival,' " Kelly said, "and then he smiled at me and said, 'I was 10 and 9.' "

Kelly is 2-3 in the rivalry, and a loss Saturday would nudge his 33-33 overall record at UCLA back below .500. That would be a referendum of its own, given the Trojans' recent struggles.

USC is in a freefall, losers of four of its last five, a former College Football Playoff contender now scraping rock bottom heading into Saturday's rivalry matchup with UCLA. Lincoln Riley may not be sitting in a seat as scorching hot as his counterpart, but the USC coach finds himself in a far less comfortable position now than he did last November.

Riley had never lost more than three games in a season before this one. Now he's lost that many in the last month, the nadir so far of an otherwise sterling career.

Although Riley's support within the university hasn't wavered, the next month — starting Saturday — will say a lot about the direction he's taking USC. He already has fired Alex Grinch, his defensive coordinator, finally making a move that fans had been demanding for more than a year.

How far the culling continues from there could depend in part on how USC's defense responds Saturday. Already some players have started to disappear from the practice field.

"I expect us to take a major step forward this weekend, I do," Riley said. "Plain and simple."

Of the two coaches, it was Kelly who managed to resurrect his defense this season. UCLA climbed from 90th in points allowed in 2022 to ninth a year later, a stunning rise that by all means should've sent the Bruins surging to the top of the Pac-12. Instead it only made them a more profound disappointment, as Kelly's vaunted offense cratered, cycling through four quarterbacks on its way to near-total futility.

Riley could sympathize with the struggle. The same had been true for USC and its defense all season.

"It's hard to time it out sometimes where it all clicks at the same time," the Trojans coach said.

The fact that UCLA clicked so quickly under new defensive coordinator D'Anton Lynn had certainly caught Riley's attention. He'll have a close-up look Saturday at Lynn, whose fast work could make him a particularly intriguing option for another reclamation project across town — or at the very least earn him a significant raise from his $1 million annual salary.

Either way, as Riley sees it, UCLA's overnight transformation on defense is proof of concept that USC can pull off something similar. Assuming, of course, he's able to bring the right defensive coordinator.

"It's come together for them," Riley said. "You look across college football, whether it's UCLA, there have been plenty of examples of when you can turn things around and grab some momentum, and you get some of the right pieces on board, both from a staff and a player perspective, that you can make really major gains quickly. It's very possible."

But neither team can be expected to change their stripes by Saturday. UCLA will lean on its elite defense, which has held eight of its 10 opponents this season to 17 points or fewer. USC will let Caleb Williams, its star quarterback, cook in what could be his last collegiate game.

While Riley raved this week about UCLA's "tremendous" defensive front led by edge rusher Laiatu Latu, Kelly piled on praise about Williams, joining the chorus comparing him to Kansas City Chiefs quarterback Patrick Mahomes.

"He's a truly special player — in all of college football and one for the ages," Kelly said. "He makes some plays where you just kind of shake your head and go, 'Oh my god.' "

Keeping pace with a Heisman winner won't be easy for Ethan Garbers, who's expected to start at quarterback for UCLA after sitting out last week's loss to Arizona State with an apparent foot injury. Where Garbers has six touchdown passes all season, Williams has six (four passing, two rushing) over his last two games.

"They have the returning Heisman winner at quarterback," Kelly said. "They can score a lot of points. We've got to be prepared for that."

That left no room for other discussion this week at UCLA, nor any reflection from Kelly on the Bruins' big picture. Was the speculation about his job a distraction to the team? "No, no at all," Kelly said.

But elsewhere, the conversation about Kelly was already carrying on, too loud now, after six seasons, to ignore.

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