sophomore, Lucas quickly established himself as USC’s most important defensive line piece, racking up a team-high 12 pressures and proving stout against the run off the edge.

But they’ll only have that different version, it turns out, for six games. Riley told media on Tuesday that Lucas is out for the season after undergoing a procedure on his leg.

Lucas limped off with an injury and was taken to the medical tent late in USC’s Week 5 loss to Minnesota, but still managing to play 38 snaps and record six tackles against Penn State last Saturday. He wasn’t seen working with USC’s defensive line group in the early period of USC’s practice Tuesday, however, and Riley clarified later that Lucas had sustained an injury to a “lower extremity.”

“Hate it for Anthony, because he’s really improved,” Riley said. “He had a really strong impact on our defense.

“He’s in a good frame of mind. We’ll be excited to get him back next year and get him rolling and build on all the progress he made. And in the meantime, it’s going to create an opportunity for some more guys to step up.”

The question is who, exactly, as USC’s defensive line room is already dangerously thin – and its front was further weakened Tuesday by the announced medical redshirt of senior linebacker Eric Gentry. Lucas was praised throughout the fall for his versatility in rotating at interior and edge spots, and both groups will feel his loss, a junior who has played more snaps than anyone else on the Trojans’ defensive line in 2024. Starting defensive tackle Gavin Meyer is banged up, carted off midway through last the loss to Penn State. Former difference-maker Bear Alexander is out of sight and out of mind, not seen at a USC practice since settling on a redshirt three weeks ago.

“You rely on the development that’s been going on the scenes, and the guys that you’ve recruited,” Riley said, when asked the plan in USC’s defensive line room with Lucas’ absence. “And maybe there’s some guys that you thought, ‘Well, maybe their role won’t be quite as much this year, maybe they redshirt’ — that, now all of a sudden, they’re going to have that opportunity.”

The most obvious name in that group is true freshman Kameryn Fountain, USC’s most highly prized recruit to come out of the 2024 recruiting cycle and a true eye-popping standout at 6-foot-6 and 265 pounds. He flashed collegiate-ready burst in a handful of snaps against Utah State in Week 2, recording a few tackles and a quarterback pressure, and stands to inherit a few looks.

“From spring to now,” defensive coordinator D’Anton Lynn said of Fountain in early September, “he’s like a different player.”

USC, too, will desperately need established names in its edge group to step up in Lucas’ absence, as the roster has continued to rank dead-last in the Big Ten in quarterback pressures for much of this 2024 season. Sophomore Braylan Shelby has been stout against the run, but after putting on 20 pounds in the offseason, has recorded just one sack and five quarterback hurries through six games.

“Probably higher than anybody on the team,” defensive ends coach Shaun Nua said in USC’s fall camp, when asked the standard for Shelby in 2024.”

“Just as high,” he continued, “same as Anthony Lucas, and any guy that has the ability to do big things.”