USC’s Matt Barkley goes to scratch on interceptions

Matt Barkley is starting over.

USC’s sophomore quarterback saw his previously unblemished touchdown-to-interception ratio take a hit in Saturday’s victory at Minnesota.

After passing for seven touchdowns without an interception in the Trojans’ first two games, he passed for two more touchdowns against the Golden Gophers but also had two passes picked off in the Trojans’ 32-21 victory.

Barkley did not expect to go the entire season without an interception.

“I guess the goal is to see how long you last before it happens,” he said after practice Tuesday. “But I’ll count at zero from here on out. Start it over and start from scratch.”

Barkley passed for 15 touchdowns with 14 interceptions last season. During spring practice and training camp, new Coach Lane Kiffin said the ratio would not be acceptable.

“We’ve improved on that,” Kiffin said, “but we’ve got to keep improving so Saturday doesn’t happen again.”

After three games, Barkley is ranked 16th nationally in passing efficiency.

“Last year, I kind of forced a lot of balls but I don’t think I’ve been doing that this year,” he said.

Barkley is a nursing a sore calf and sore neck after being thrown to the ground on a play in which the Golden Gophers were called for a facemask penalty.

He said he would be fine when the Trojans open Pacific 10 Conference play Saturday at Washington State.

Welcome to the Pac

Kiffin was not surprised by the announcement that Colorado would join the Pac-10 in 2011, rather than 2012.

Utah also will join the Pac-10 next year.

“I would assume that adds a championship game and more competition to an already very deep conference,” he said.

Asked whether he liked the format that allows for a championship game, he said, “Sure, if we’re in it. I like it a lot.”

NCAA sanctions against the Trojans included a two-year bowl ban.

The school is appealing to reduce the ban to only this season.

Quick hits

Defensive lineman Armond Armstead was limited because of a shoulder injury. … Junior safety Drew McAllister, who has been limited because of a hip injury, will have surgery and redshirt, Kiffin said. … Safety Patrick Hall practiced after being reinstated from a three-week suspension from team activities.

gary.klein@latimes.com

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