Riley vs. the Trojans secondary: USC has struggled on defense as a whole this year, but it is much worse against the pass -- see a young secondary that tackles poorly -- than against the run -- see a talented, if thin, front-seven. Last week, Cal's senior QB Kevin Riley had a forgettable game passing, but he's going to have to throw well to win at USC. The Trojans rank 116th in the nation in passing defense (287.5 yards per game), so that is a weakness Riley must attack. While Riley has been inconsistent throughout his career, he also has posted plenty of efficient performances. He'll need one of those for the Bears to win.