USC vs. Wisconsin three things to watch: Alex Grinch returns to L.A.

When Lincoln Riley was hired at USC in 2021, one of his first calls was to Alex Grinch. The defensive coordinator had already helped turn around his Oklahoma defense, and in the process, the two coaches had come to trust each other. Their families got close. So when Riley arrived in L.A., on an early-morning plane that November, Grinch was on the same flight.

It turned out to be a rocky ride for Grinch at USC. He lasted less than two seasons and presided over two of the worst defenses in school history. But when the two coaches reunite Saturday at the Coliseum — this time, with Grinch wearing a different shade of red — Riley won’t be thinking about how things ended for him, less than a year ago, at USC.

“It’ll be good to see him,” Riley said. “It’ll certainly be unique, being on opposite sidelines, with all the good times and great memories we had together, all the years working together.”

The two coaches had worked together from 2019 to 2023, between stints at Oklahoma and USC. Plenty of time certainly for Grinch, who now coaches Wisconsin’s safeties, to understand exactly how Riley’s offense ticks.

“Coach Grinch has a good familiarity with what we’ve done,” Riley said. “But I still think the game comes down to players and who executes the best on Saturday afternoon. I think we’ve prepared hard, but we know it’ll be a good challenge going against a defense that he’s obviously a part of.”

That Wisconsin defense, for what it’s worth, now ranks 16th out of 18 teams in the Big Ten in scoring defense (23 points per game).

Here’s what to watch as No. 13 USC faces Wisconsin in its Big Ten home opener on Saturday at 12:30 p.m. PDT in a game airing nationally on CBS (Paramount+).