Pac-12 Football 2017: 5 teams that will be on upset alert in Week 4

USC won its first two games by 18 points apiece, but only the win over Stanford was convincing in any way. In the season opener, Western Michigan played the Trojans tight into the fourth quarter. Clay Helton’s team managed to pull away late for a comfortable-looking margin of victory, but getting there was anything but comfortable.

Then there was last week’s performance, when USC needed a field goal on the last play of regulation just to force overtime. They survived on their home field in a double-overtime victory, but they merely eked past the Longhorns.

Champions inevitably will have a close game or two along the way, but they also tend to dominate lesser competition. For the Trojans, teams like Western Michigan and this year’s Texas squad are supposed to be fodder on the path toward a title. Instead, they were roadblocks that nearly derailed Southern California.

They already have one Pac-12 win over the Cardinal, but now USC takes to the road for the first time this year to play Stanford’s Bay Area rival. California has started the year 3-0 on the strength of a defense that is generating three turnovers per game. Sam Darnold has already thrown six interceptions on 108 passing attempts. If he is as careless with the football as he has been in the first three games, the Golden Bears will pounce on the 17-point favorites at Memorial Stadium.