The Key Position Driving USC’s Defensive Improvement This Season

The cornerback room was a concern for the USC Trojans through the first month of the season, but since the first bye week, its a position group that has made tremendous strides and led to improved Southern Cal defense.

Aug 30, 2025; Los Angeles, California, USA; Southern California Trojans head coach Lincoln Riley watches from the sidelines against the Missouri State Bears in the first half at United Airlines Field at Los Angeles Memorial Coliseum. Mandatory Credit: Kirby Lee-Imagn Images | Kirby Lee-Imagn Images

USC walked off the field in a week 5 loss to Illinois having allowed 364 passing yards. It had been a cumulation of some early season struggles that were largely masked by a dominant pass rush. 

Communication in the secondary was an issue through the first month of the season, having allowed several big plays in the pass game because of a bust in coverage. 

And the Trojans headed into their first bye week in late September with some major questions in the backend of their defense, particularly at cornerback. 

Resetting at the Bye Week

Aug 30, 2025; Los Angeles, California, USA; Southern California Trojans head coach Lincoln Riley watches from the sidelines against the Missouri State Bears in the first half at United Airlines Field at Los Angeles Memorial Coliseum. Mandatory Credit: Kirby Lee-Imagn Images | Kirby Lee-Imagn Images

The bye week allowed them to get back to the basics. And since returning to action against Michigan on Oct. 11, it’s been a new-look USC secondary. Southern Cal has allowed under 200 passing yards in each of their last three games. 

Only Michigan quarterback Bryce Underwood has surpassed that mark in the four games since that bye, when he threw for just 207 yards in a USC rout. 

It’s a unit that has made tremendous strides over the past month under the tutelage of secondary coach Doug Belk and cornerbacks coach Trovon Reed.

Redshirt freshman Marcelles Williams, a local product from St. John Bosco (Calif.), has settled in as the starter opposite of redshirt senior DeCarlos Nicholson since stepping into that role in week 4. 

Nov 1, 2025; Lincoln, Nebraska, USA; Southern California Trojans cornerback Marcelles Williams (25) breaks up a pass to Nebraska Cornhuskers wide receiver Nyziah Hunter (13) during the fourth quarter at Memorial Stadium. Mandatory Credit: Dylan Widger-Imagn Images | Dylan Widger-Imagn Images

Williams has been a standout since he arrived on campus as an early enrollee in the 2024 recruiting class. He immediately made an impression on the veterans last spring and USC coach Lincoln Riley raved about his progression during his first season with the program on multiple occasions heading into the fall.

The former four-star recruit has shown a steady growth this season the more live game reps he gets under his belt. All of that came together in the Trojans week 10 victory over Nebraska, with Williams put together his best performance in a Trojans uniform.

The Cornhuskers challenged the young defensive back several times and he responded by allowing just 13 receiving yards on the night. 

“He just went out there and did his thing. Did what he was supposed to do as a player. He held his own as a man,” said USC defensive end Kameryn Crawford after the game. 

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Nicholson was the Trojans highest-graded defensive player, according to Pro Football Focus in last Friday night's win over Northwestern after finishing with two pass breakups. 

Nicholson, a former high school and JUCO quarterback, has become a natural at the position with his 6’3” frame. And as Nicholson and Williams have grown this season, so has the defense as a unit.

Oct 19, 2024; College Park, Maryland, USA; Southern California Trojans cornerback DeCarlos Nicholson (17) warms cup before the game against the Maryland Terrapins at SECU Stadium. Mandatory Credit: Tommy Gilligan-Imagn Images | Tommy Gilligan-Imagn Images

"As the corners have really started to settle in and play some good ball, it gives coach [D’Anton] Lynn the opportunity to call several more things and throw different looks at opposing offenses and quarterbacks," Riley said.

Lynn has an exotic blitz package that he's been able to unleash with his trust in the cornerback room growing by the week. And as a result, the Trojans have held its opponents to 17 or fewer points in three of their last four games.

Riley had been known to get into shootouts on a weekly basis since he became the head coach at Oklahoma in 2017 but that is no longer the case in 2025.

Braylon Conley Regains His Confidence

Nov 7, 2025; Los Angeles, California, USA; Southern California Trojans head coach Lincoln Riley watches game action against the Northwestern Wildcats during the second half at the Los Angeles Memorial Coliseum. Mandatory Credit: Gary A. Vasquez-Imagn Images | Gary A. Vasquez-Imagn Images

Williams went down in the second quarter with an injury against Northwestern and Braylon Conley, who had not taken a single snap at cornerback since his rough outing against Illinois on Sept. 27, was called upon. 

It wasn't perfect, with the Lone Star State native being flagged for pass interference and giving up a 32-yard pass, but overall, it was clear this a much better player that was on the field six weeks ago against the Fighting Illini.

As the new corner in the game, Northwestern tried to pick on Conley and similar to Williams the week prior, he responded very well. Conley looked much more comfortable with his technique and was a physical presence in run support. He had regained his confidence, an essential part of playing the position. Williams did eventually return to the game in the fourth quarter.

“Braylon Conley came in made a lot of great plays, tackled well, competed,” said USC safety Kamari Ramsey after the game. “That's that's all you can ask for. Just compete. Get a flag. Just move on, next play mentality. So he did a great job of that.”

Willians and Conley are the perfect example of player development at USC, something that had been sorely missing in the program for years. The players that were on the field in September, are not the same players fans have seen in the month of November.