USC faces a new challenge against Minnesota’s MarQueis Gray

USC knows all about Minnesota’s MarQueis Gray.

Last season, the 6-foot-4 Gray caught four passes, including a touchdown, in the Golden Gophers’ loss to the Trojans at Minneapolis.

But that game tape won’t do USC much good as the Trojans prepare for Saturday’s opener at the Coliseum.

Gray, a 240-pound junior, has been moved to quarterback by first-year Coach Jerry Kill.

Gray has not played the position regularly since he was in high school in Indianapolis.

Last season he had 110 yards and a touchdown in 23 carries out of the wildcat formation. And he has completed eight of 23 passes for 86 yards and a touchdown, with one interception.

USC freshman receiver George Farmer played quarterback for the scout team last week to give the Trojans a look at the kinds of problems Gray could present.

USC is not the only team that has struggled against mobile quarterbacks — see the 2009 and 2010 performances by Washington’s Jake Locker and Stanford’s Andrew Luck against the Trojans — but the thought of one who even approaches the size of former Texas star Vince Young is enough to put USC players on edge.

“As a linebacker,” senior Chris Galippo said, “usually you don’t want to be chasing around fast quarterbacks.”

The right stuff

While the search for a left guard continues, John Martinez is on track to start at right guard.

Martinez, a third-year sophomore from Utah, came to USC as a center. Coaches moved junior Khaled Holmes to that spot during spring practice and Martinez has taken advantage of an opportunity to play alongside him.

The 6-2, 290-pound Martinez won the job because of his consistency, Coach Lane Kiffin said.

Still, right guard is one of 14 positions on USC’s depth chart that does not feature a designated starter.

At tailback, Dillon Baxter, Curtis McNeal, D.J. Morgan and Amir Carlisle are listed as possible starters.

Quick hits

USC announced that there will be Spanish-language radio broadcasts this season on KTNQ 1020 AM. Adrian Garcia Marquez, Jorge Caamano and Alex Russo make up the broadcast team. It is the first year USC has had a Spanish-language broadcast since 2007. … A “Fall Sports Rally” that will include football players and other fall-sport athletes will be held Thursday at the Galen Center at 7 p.m. The event is open to students, alumni and fans.

gary.klein@latimes.com

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