Can USC’s defense find its stride during a crucial, final stretch?

USC cornerback DeCarlos Nicholson breaks up a pass intended for Michigan’s Andrew Marsh last month.It was two years ago this month, with USC’s defense at an unthinkable nadir, that Lincoln Riley finally decided to fire Alex Grinch, his first defensive coordinator.

“I am that committed, and we are all that committed to playing great defense here,” Riley said in 2023. “Whatever it takes to get that done, that’s what we’re going to do.”

Not everyone took Riley’s comments seriously at the time.

“There’s a school on the West Coast right now that’s going to re-commit to defense,” Iowa coach Kirk Ferentz said a month later. “You give up [46] to Tulane last year in a bowl game — at a place where…