Defense. That has been the most significant roadblock for USC Trojans coach Lincoln Riley since his arrival in Los Angeles. Despite producing some of the most explosive offenses in college football, Riley’s tenure at USC has been consistently hamstrung by defensive setbacks. However, this season Riley feels even more confident in his team's potential across the board.“I do feel differently this year in terms of the quality of players, returning starters, the freshmen, some of the transfers that we've added,” said Riley during Big Ten Media Days. “There's just a ton of competition. We have a lot of guys on both sides of the line of scrimmage that we feel like we can win with and dominate with. We just do.”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 | IMAGN IMAGES via Reuters ConnectWith the addition of Hall of Fame coach Gary Patterson taking over as defensive coordinator, six returning defensive starters, and new talent out of high school and the transfer portal, the Trojans appear poised to cure their Achilles' heel."I certainly will give you what has changed, is I do believe we're more equipped than at any point in the previous few years," Riley said. "That's not a hope or a wish. Those are facts, and there's a lot of facts to back that up."Where USC’s Defense Needs to ImproveUnder Riley's leadership, the Trojans’ offense has been dominant. The defense, however, has been a different story. USC’s defense finished outside the top 90 nationally in scoring defense in 2022 and outside the top 120 in both scoring and total defense in 2023 before showing improvement under defensive coordinator D'Anton Lynn over the past two seasons.However, even with that progress, one glaring issue remained in 2025: stopping the runaway from home.“We did not stop the run enough on the road,” said Riley of the Trojans' 2025 defensive performance.Sep 20, 2025; Los Angeles, California, USA; Southern California Trojans defensive end Jahkeem Stewart (4) reacts after a defensive play against the Michigan State Spartans during the first half at the Los Angeles Memorial Coliseum. Mandatory Credit: Gary A. Vasquez-Imagn Images | IMAGN IMAGES via Reuters ConnectUSC allowed 121.3 rushing yards per game at home but 168.8 on the road and at neutral sites, while opponents averaged 4.63 yards per carry away from Los Angeles compared to 4.06 at home.In USC's four losses, opponents rushed for 193.3 yards per game at 5.12 yards per carry and scored 10 rushing touchdowns. USC couldn't consistently stop the run on the road, and it proved costly in close conference games.Those recurring defensive issues are a big reason why Riley brought in one of the most respected defensive minds in college football, Gary Patterson.Gary Patterson Brings a New Defensive Identity to USCPatterson built his reputation by developing disciplined, physical defenses during his two decades at TCU, and now his job is to help USC take the next step.Patterson could very well be the missing piece the Trojans need in order to establish themselves as a national championship contender and make the College Football Playoff in 2026.TCU coach Gary Patterson during a college football game between the University of Oklahoma Sooners (OU) and the TCU Horned Frogs at Gaylord Family-Oklahoma Memorial Stadium in Norman, Okla., Saturday, Oct. 16, 2021. Oklahoma won 52-31.