OU's Samaje Perine (32) runs after a catch during a drill at spring football practice for the University of Oklahoma Sooners in Norman, Okla., Monday, March 23, 2015. Photo by Nate Billings, The Oklahoman

NORMAN — Oklahoma’s Samaje Perine established himself last season as one of the best running backs in college football, and did so with a powerful, tough running style that sometimes left opposing defenders injured.

It’s the way Perine has always run, both in practice and in games, for as long as he’s played football. That’s why when he showed up for the Sooners’ annual spring game three months ago, he was a little confused.

Perine, who was the Big 12’s leading rusher as a true freshman last season, only carried the ball three times for four yards in the spring game and defenders weren’t allowed to hit him. He wore a red jersey with blue numbers, signaling “no contact” to defensive players.

“I go in and I had the blue numbers, and I said, ‘What is this?’” Perine told The Oklahoman in a recent telephone interview.