CHARLOTTESVILLE, Va. — As USC begins its quest for a third appearance in the Bowl Championship Series title game in five seasons, LA Times staff writer Gary Klein looks at some of the key issues and matchups when the Trojans play the Cavaliers on Saturday.

Could be a runaway:

So much focus has been on the quarterbacks — would Mark Sanchez be ready for USC? Who will be Viriginia's starter? — yet this game probably will be decided by the running game.

Virginia must control a four-headed USC tailback monster of Joe McKnight, Stafon Johnson, C.J. Gable and Allen Bradford — and do it without defensive end Chris Long, the No. 2 pick in the NFL draft.

A USC defensive line sans nose tackle Sedrick Ellis, the No. 7 overall pick, will try to stop running back Cedric Peerman, who was the Atlantic Coast Conference rushing leader before a foot injury ended his 2007 season.

About those QBs ...

Sanchez will be under center for USC, with Aaron Corp as the first reserve. Virginia has not named a starter. Sophomore Peter Lalich played in eight games last season. Third-year sophomore Marc Verica has no college game experience.

Another option for the Cavaliers would be senior Scott Deke, who led Los Angeles Loyola High to the 2003 Southern Section Division I title, passing for three touchdowns and intercepting a pass in the championship game.

Watch the blind side:

For the first time in four years, someone other than Sam Baker will open the season protecting USC's quarterback at left tackle. Charles Brown, a 6-6, 295-pound junior, made his only career start last season on the right side.

For Virginia, left tackle Eugene Monroe, a 6-foot-6, 315-pound senior, is a certain first-round NFL draft pick, according to Carroll.

"He was the most perfect-looking guy we saw coming out of high school ⁄in Plainfield, N.J.‹," Carroll said. "Great athlete, good student, he was full grown ... a long time ago."

Caller I.D.

There's the "Sam", the "Mike" and the "Will," otherwise known as the strong-side, middle and weak-side linebackers.

And then there's Buck.

That's the nickname USC designated for the extra linebacker in Virginia's 3-4 scheme, the one that could wreak havoc in the backfield if not properly identified before each snap by sophomore center Kristofer O'Dowd.

"It's all about communication," O'Dowd said.

Virginia senior Clint Sintim had nine sacks last season and had the highest per-game average of any linebacker in college football.