Tampa Bay Buccaneers rookie edge rusher David Walker has a torn ACL and will miss the season, coach Todd Bowles confirmed Monday.
Walker, the Bucs' fourth-round pick in this year's draft, suffered the injury during Friday's practice.
The 6-foot-2, 260-pound outside linebacker was expected to serve a backup role at the start of the season behind Bucs starting outside linebackers Haason Reddick and Yaya Diaby.
"He was making a big impact early," Bowles said, according to the team's website. "Obviously, we were counting on him doing a lot of things, but other guys are going to have to step up. I told him he has to look at this like a redshirt year. It's unfortunate. It didn't look like it was too much on film, but it ended up being that."
Walker was a three-time All-American at Central Arkansas and led the FCS with 23 tackles for loss last season. He recorded 10.5 sacks last season and was named the Buck Buchanan Award winner, given to the best defensive player in the FCS.
ESPN's Dan Graziano contributed to this report.