PITTSFORD, N.Y. (AP) Rex Ryan's new-look defense is running out of rookie starters.
The Bills' two top draft picks are now sidelined with injuries.
The team announced Wednesday that linebacker Reggie Ragland will have surgery to repair a torn ligament in his left knee. Ryan said he expects Ragland to miss the entire season.
Ragland was Buffalo's second-round pick out of Alabama. The Bills are already down their first-round pick, linebacker Shaq Lawson, who is expected to miss at least the first month of the season recovering from shoulder surgery in May.
''Well, we were excited about those two guys. Obviously, we think they're rare talents and that's not going to change either based on an injury,'' Ryan said following practice. ''It's just unfortunate that we've got to be a little more patient than maybe we wanted to.''
Ragland was hurt during practice Friday. He was going after a ball carrier on a run play when he pulled up suddenly and went to the ground without being hit.
Initial tests were inconclusive because of swelling around the knee. The severity of the injury was revealed after a follow-up test.
The Bills thought so highly of Ragland that they considered selecting him with their first pick, 19th overall. They instead chose Lawson, a highly touted pass rusher out Clemson whose stock dropped because of concerns he might need shoulder surgery to repair an injury that nagged him in college.
In the second round, the Bills traded up eight spots to select Ragland with the 41st pick.
Both were immediately pegged as starters on a defense being overhauled after it underperformed during Ryan's first season last year.
Ragland spent the entire offseason playing one of two middle linebacker spots, alongside returning starter Preston Brown.
Veteran free agent addition Zach Brown will replace Ragland. The Bills also restocked the position by signing veteran free agents Brandon Spikes and David Hawthorne on Sunday.
Lawson was supposed to immediately step in to fill the outside position left open after the Bills cut Mario Williams in March. Lawson's backup, veteran Manny Lawson, is also hurt. He's expected to miss most of the preseason with a partially torn pectoral muscle.
Despite the injuries, Ryan is sticking with the offseason vow he made in saying Buffalo's defense will be better from last year, when it ranked 20th in yards allowed and managed 21 sacks - a franchise-low for a 16-game season.
''I've said all along our defense will be much improved, and I'll stand by that,'' Ryan said. ''It's really unfortunate for the young man and for our team because we know he's a fine player. But guys will step up.''
NOTES: WR Greg Salas left practice with a hamstring injury. ... CB Sterling Moore left practice with a head injury and is being monitored for a concussion. ... The Bills practice Thursday night before opening their preseason hosting Indianapolis on Saturday.
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