No. 21 USC heads to No. 17 Washington for a cross-divisional litmus test  in a Pac-12 afternoon top-25 matchup Saturday. The Trojans will be looking to build off of their home upset over Utah. However, USC could potentially be down yet another quarterback with Kedon Slovis suffering a possible concussion against the Utes. 

The Huskies can get back on the right track in the Pac-12 race with a win after dropping its opener to Cal. Meanwhile, 

Can USC pull another upset and take more heat off of coach Clay Helton's seat? Or will Washington win big as a double-digit favorite? Here's how to watch Saturday's game and the storylines to follow. 

Storylines

Washington: The Huskies have developed their own reputation as "DBU" in the Northwest and they've put some real dudes in the pros. How this group performs against USC's passing offense will be fascinating to watch. Washington has the Pac-12 second-best passing defense and all four of the team's picks have come from the secondary. Of course, no good secondary works alone; Washington will need to continue to be solid up front against a USC running attack that has been more miss than hit lately. We know what Washington's offense can do, but the Huskies' defense will be the side of the ball to watch in this matchup. 

USC: Who starts at quarterback? In all likelihood it'll be Matt Fink, who came off the bench to help lead USC to victory over Utah last week. Kedon Slovis is still going through concussion protocol and his status for Saturday's game is very much up in the air. Having an extra week to prepare with the first-team offense will be helpful for Fink -- offensive coordinator Graham Harrell has shown he can win with just about anybody taking snaps -- but going on the road against a talented Huskies defense is a different animal. USC's wideouts are as talented as any group in the country and Fink can deliver jump balls to them, but I don't know if that's a sustainable offensive plan. 

Viewing information

Date: Saturday, Sept. 28 | Time: 3:30 p.m. ET
Location: Husky Stadium -- Seattle
TV: Fox | Live stream: fuboTV (Try for free)

Game prediction, picks

Other than its weather-delayed loss to Cal, Washington has handled its business. USC is theoretically good enough to win this game, but if Fink is indeed the quarterback, I don't think he gets away with the deep throws that he did against Utah. Plus, who knows what you'll get out of the Trojans on the road. Pick: Washington (-10.5)

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