LOS ANGELES (AP) Replacing Leonard Williams is the glaring challenge for Southern California's defense.
Williams was the last and perhaps greatest find of former assistant coach Ed Orgeron's decade-long association with the Trojans. The star defensive lineman was a relentless force, tallying 218 tackles, 36 1-2 tackles for loss and 21 sacks in three seasons before being selected No. 6 overall by the New York Jets last spring.
Replicating Williams' production will require multiple contributions, and the improving USC secondary is set to offer some unexpected assistance.
If corners and safeties can better cover opposing receivers, the pass rush has more time to get to the quarterback. USC had just 33 sacks last season, 24 in nine Pac-12 Conference games, despite Williams' dominating presence. Inexperience among the defensive backs was certainly a contributing factor to the lack of quarterback hits and hurries.
''It's a marriage,'' defensive line coach Chris Wilson said. ''It's not one or the other. You can't get pressures on quarterbacks without both parties doing their jobs.''
Based on what it showed in USC's first scrimmage of fall camp, a secondary that allowed a surprising 305.9 yards passing per game in conference play last season should be able to do its part.
Freshman corner Iman Marshall, freshman safety Marvell Tell and sophomore corner Jonathan Lockett each had interceptions in the scrimmage. Standout three-way contributor Adoree Jackson would almost certainly have joined that group, but USC quarterbacks have all but given up trying to complete passes against the sophomore corner.
New additions should also be a factor on the defensive line, with freshman defensive end Christian Rector singled out for his early development. After having to rely on Williams and returning seniors Antwaun Woods, Claude Pelon and Delvon Simmons almost exclusively to man the line last season, getting contributions from more players should give the USC defensive front more energy in the late stages of games, as was certainly the case in the scrimmage.
''I think we started out slow but we got better and dominated towards the end,'' defensive tackle Kenny Bigelow said.
Making use of that increased depth is all but mandatory in a conference known for its up-tempo offenses, but Wilson said the benefits are negligible if there is a dramatic drop-off in productivity when substitutes are in the game. Wilson would like to use seven or eight linemen in every game and sees ''anywhere from eight to nine guys that can contribute in multiple situations.''
''Obviously, the numbers help, but the biggest key is we've got quality numbers,'' Wilson added. ''It's quality over quantity. It's not like we've got a bunch of guys out there filling roles. We've got guys who are very capable of playing at a high level.''
Bigelow is set to be one of those contributors. A former five-star recruit, Bigelow used his redshirt during the 2013 campaign and then missed last season because of a knee injury. After two years on the bench, he is hungry to play - and to pick up the slack created by Williams' departure.
''Everyone knows Leonard did some great things here,'' Bigelow said. ''But I think we definitely have the depth and the talent now to be able to play without him.''