USC opened the season with designs, however unrealistic, on finishing unbeaten.
Now, it will be a challenge for the Trojans to remain two games above .500.
USC, 5-3 overall and 2-3 in the Pacific 10 Conference after Saturday night's loss to top-ranked Oregon, plays three of its final five games on the road.
The Trojans play their last Pac-10 home game this week against talented-but-unpredictable Arizona State and then finish with games at No. 13 Arizona and Oregon State, a nonconference home game against Notre Dame and the season finale against UCLA at the Rose Bowl.
USC has not finished with a losing overall or conference record since 2000, Paul Hackett's final season as coach. In 2001, before the Pac-10 adopted a full round-robin schedule, the Trojans were 1-3 in Pac-10 play before rallying to win their final four conference games.
Coach Lane Kiffin said Sunday that he did not consider motivation an issue as the Trojans move forward.
But there could be lineup changes.
"We are going to look at some things," Kiffin said. "We are going to look at two spots, specifically, on making sure that we're playing the best player there."
Kiffin declined to specify which spots were under review.
But the back seven on defense merit scrutiny.
After giving up 599 yards against Oregon, USC fell to 98th among 120 major college teams in total defense and 114th in pass defense.
Oregon quarterback Darron Thomas, who passed for four touchdowns, repeatedly burned USC with passes over the middle — many after play-action fakes to LaMichael James, who rushed for 239 yards and three touchdowns.
"Their scheme counts on defenses wearing out and making mistakes just like we did," cornerback Shareece Wright said after the game. "They capitalize on those chances, and that's how they win."
Said Kiffin: "If you don't slow down the run somewhat, you don't have any chance. With that you become vulnerable."
Kiffin said that USC quarterback Matt Barkley, who had two passes intercepted and also had a mistimed snap bounce off him, "didn't play very well." But the coach blamed himself for not helping the sophomore with better play-calling.
"They blitzed over 80% of the time," Kiffin said of Oregon. "I should have helped him out with some easier completions."
Something to build on
Kiffin said a new $70-million athletic building that will house football coaches' offices, a weight room and other amenities was "a giant step" for the program.
USC announced Saturday that it planned to break ground on the 110,000-square foot building in January.
Kiffin said the project would help with recruiting.
"The only negative we've dealt with over the years [was] our facilities compared to other people," he said. "Now, we won't have that."
The Trojans suffered no major injuries against Oregon, Kiffin said…. USC resumes practice Tuesday.