CORVALLIS — Watching Jermar Jefferson during the first few weeks of August camp, it was apparent the young running back was going to make some kind of an impact for the Oregon State football team.

Nobody would have envisioned, however, he would be the Beavers’ leading rusher and set the school record for rushing yards by a true freshman.

When starter Artavis Pierce went down with an injury in the second game of the season, Jefferson took the reins and became one of the bright spots for the Beavers in a disappointing season.

Jefferson burst onto the scene with a 238-yard rushing performance in that win over Southern Utah, his first game at Reser Stadium.

He followed up three games later with a 254-yard effort at Arizona State and now has the second- and fourth-highest single-game rushing performances in Oregon State history.

He has eclipsed the 100-yard mark seven times, including the last two games, and set the OSU true-freshman mark last Saturday at Washington, surpassing the mark of 1,253 set by Jacquizz Rodgers in 2008.

Jefferson has 1,316 yards this season heading into Friday’s Civil War, an average of 119.6 per game.

He was on pace earlier this season to break the Pac-12 freshman record of 1,546 yards set by Oregon’s LaMichael James in 2009.

Not bad, considering he had just two carries in one game and only eight in another.

“He’s been one of the pleasant surprises and we’re excited for the future with him for sure,” offensive coordinator Brian Lindgren said.

Offensive line coach and run-game coordinator Jim Michalczik has been impressed with the way Jefferson has learned how to be a college running back.

“Early on I think (running backs coach) Mike Pitre has done a great job with him understanding every play is not going to be a touchdown,” Michalczik said. “Go get the hard yards. And I think he’s done a heck of a job just running, falling forward. Sometimes those 2-, 3-yard gains open up those 7, 8, 20s. If you’re always trying to get the touchdown you’re not going to get it.”

Jefferson has 12 touchdowns but has been shut out of the end zone the last five games.

Lindgren, Michalczik and head coach Jonathan Smith all said Jefferson has made the most improvement in pass protection.

Lindgren said that shows Jefferson’s maturity as the season has progressed.

“It’s not only when you’re touching the ball (but) are you a difference maker and a factor when the ball is going away from you,” Lindgren said. “You have to step up and pick up a pressure on third down.

“He’s still got a ways to go in that area but I think he’s started to take pride in that and really work at developing that and you’ve seen his growth in that since the beginning of the year.”

Added Michalczik: “I think he’s done a good job to become a college running back.”

Smith said he has been impressed with Jefferson’s ability to maintain his body though the course of the season because he has not had an offseason to train at the college level.

Jefferson has carried the ball 218 times and also has 24 receptions (for 155 yards), so he has carried quite a load.

Despite being a little banged up, Jefferson has made it hard for the Beavers to take him off the field.

“It’s hard to on Saturday when he’s running the ball,” Lindgren said, “because when he touches it he has the opportunity to turn it into a big play.”