PITTSFORD, N.Y. (AP) The Buffalo Bills are running out of backups to their backups at linebacker.
IK Enemkpali sustained a season-ending right knee injury, and he will be released after being placed on the waived/injured list on Monday. The move freed up a roster spot for the Bills signing Kroy Biermann to address their already-thin pass-rushing depth.
Enemkpali tore his anterior cruciate ligament in the second quarter of Buffalo's 19-18 preseason-opening loss Indianapolis on Saturday. His foot caught in the turf and he fell awkwardly while being blocked by Colts lineman Jonotthan Harrison.
Enemkpali was playing in place of projected rookie starter Shaq Lawson, who will miss at least the first month of the season because of shoulder surgery. Lawson's primary backup, Manny Lawson, is expected to miss a few more weeks recovering from a partially torn pectoral muscle.
''It's a concern,'' coach Rex Ryan said. ''I think we'd all feel better if Manny was practicing. But he's not. And until he does, you don't have that comfort level.''
Until Lawson returns, Ryan intends to shift Lorenzo Alexander into the starting spot. Though Alexander has experience at the position, Ryan planned to have the offseason free-agent addition focus more on his various special teams duties.
Biermann is listed at 6-foot-3 and 255 pounds, and spent his first eight NFL seasons in Atlanta. He had 2+ sacks and a forced fumble in 16 games, all as a backup, last season.
Overall, he has 23+ sacks and 37 tackles for a loss in 114 games, including 37 starts.
Enemkpali's tenure in Buffalo ended a year since Bills claimed him off waivers. The addition was notable coming a day after Enemkpali was released by the New York Jets for punching and breaking the jaw of quarterback Geno Smith during a locker-room confrontation.
The Bills are also thin at inside linebacker with projected rookie starter Reggie Ragland to miss the season with a torn ligament in his left knee. The injury led to Buffalo signing Brandon Spikes and David Hawthorne on Aug. 7.
Later in the day, the Bills bulked up their defensive line by signing Brandon Deaderick and Alameda Ta'amu. Deaderick did not play in the NFL last season, but has five seasons of experience split between New England, Jacksonville and New Orleans. Ta'amu was cut 10 days ago by Kansas City. He spent 2013 and `14 with Arizona before being cut by the Cardinals before the start of last season.
Buffalo freed up roster room by releasing receiver Leonard Hankerson, who had several dropped passes against Indianapolis last weekend, and defensive tackle T.J. Barnes.
On the bright side, backup running back Karlos Williams passed his physical and practiced for the first time Monday.
Williams was overweight when reporting to training camp, and spent the past two weeks working out individually while on the team's active/non-football injury list.
Williams' weight issues date to June when he reported for the team's mandatory minicamps. He blamed the weight gain on snacking with his pregnant fiancee so she didn't have to eat alone.
The second-year player's troubles mounted last month, when the NFL suspended Williams for the first four games of the regular season for violating the league's substance abuse policy.
Williams made a splash as a rookie backing up starter LeSean McCoy last season. He had 517 yards rushing and scored nine touchdowns, including two receiving.
Williams called it difficult missing the first two weeks of camp, and said it will be even tougher to miss the first month of the season.
''There's no way you can really describe that feeling,'' he said. ''It's going to be tough. And it's a process you have to live and learn. I'm learning from it, and it's time to move on.''
As for staying in shape, Williams said he's altered his eating habits by cutting out big meals, especially late at night.
He has also leaned on teammates for advice, including defensive tackle Marcell Dareus, who had several off-field issues two years ago. He's also talked to defensive tackle Kyle Williams, who has five children, about how he balances family and his career.
''I pretty much got that I can't take care of my family if I don't take care of myself first,'' said Williams, who has four children. ''So that's really something that I'm trying to change about the atmosphere of my family now.''
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