Kevin Graf ready to anchor USC’s offensive line

Kevin Graf has been a fixture at USC spring practice for 13 years. In the late 1990s and early 2000s, the over-sized grade schooler roamed the sidelines and end zone while his brother Derek toiled as an offensive lineman for the Trojans.

The sounds of gravel-voiced defensive line coach Ed Orgeron and former offensive line coach Tim Davis still reverberate a decade later.

“My earliest memories of ‘SC are being out at practice and hearing them yelling at each other across the field,” Graf said. “Good times.”

Graf, 20, attended workouts as a hopeful recruit while still in high school. Two years ago, as a redshirt offensive tackle, he learned while playing behind future first-round picks Tyron Smith and Matt Kalil. And last spring, he was an ever-present observer while recovering from shoulder surgery.

Now, as USC opens spring practice Tuesday, the 6-foot-6, 295-pound Graf will be perhaps the most scrutinized player for a team that is expected to contend for the Pac-12 Conference championship.

With Kalil moving on to the NFL, Graf gets the first shot at replacing him at left tackle. His job: protect the blindside of quarterback Matt Barkley, the Trojans’ most valuable asset.

“I’m blocking, hopefully, for the next Heisman [Trophy] winner at ‘SC,” said Graf, whose father, Allan, played guard for the Trojans in the early 1970s. “I take my job very seriously and I want to keep him clean.”

Graf returns to the left side after starting every game last season at right tackle. But switching sides shouldn’t be a problem. Graf played almost exclusively on the left side throughout high school.

“I’m a lot more comfortable,” he said.

Time will tell whether Barkley and Coach Lane Kiffin feel the same way.

Kalil, a top-three pick in next month’s NFL draft according to some projections, did not give up a sack last season.

Barkley said he was confident in all his linemen and had one main goal for spring workouts.

“To be a coach on the field,” he said, “and to take that mental side of the game to the next level.”

Last season, Kiffin rarely complimented the play of any offensive linemen other than Kalil or center Khaled Holmes, especially after the Trojans lost early in the season at Arizona State.

But he expressed confidence in Graf’s ability to protect Barkley.

“Kevin is a smart player and has gotten himself into even better shape,” Kiffin said. “He struggled early at Arizona State but really improved a lot toward the end of the year, just like most first-year starters.”

Sophomore Aundrey Walker will replace Graf at right tackle but also could get looks on the left side, especially if Graf struggles.

Walker, since the end of last season, has made the most noticeable physical transformation of any Trojans player.

After reporting last season to USC weighing 375 pounds, the 6-6 Ohio native experienced difficulty finishing practices. He has since dropped 60 pounds.

“His transition has been phenomenal,” Kiffin said. “He looks like a completely different person.”

Walker said he feels like one too.

“It was just my time, dedication and hard work,” he said. “I can’t be great at my position or get the most out of my ability playing at 365. I can feel it. I’m more in shape.”

Walker may be a future left tackle but said he was happy to get his first opportunity on the right.

“It really doesn’t matter,” he said, “as long as I’m on the field.”

gary.klein@latimes.com

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