Buffalo Bills wide receiver Stevie Johnson left practice after injuring his left hamstring Friday morning.
Johnson, Buffalo's top receiver, pulled up on a route during a red zone drill two hours into practice. He was evaluated by Buffalo's training staff and walked slowly to the locker room assisted by two people.
Bills Coach Doug Marrone said after practice that he did not know the severity of the injury and that the former University of Kentucky star will be evaluated by Buffalo's doctors.
"It would be a major concern when we talk about it during the season, but right now, I think a veteran player that has proven himself, we'll just see what the doctors say and it is what it is," Marrone said. "We'll deal with it from there."
Johnson has had some issues with injuries in recent years. He missed several spring practices due to a back injury and underwent groin surgery last off-season.
Any prolonged absence would be a concern as Buffalo tries to establish a fast-paced, up-tempo system under new offensive coordinator Nathaniel Hackett. Johnson is the team's only established receiver and has had three consecutive 1,000-yard seasons. Last year, he led the Bills with 1,046 yards receiving.
The injury does present an opportunity for Buffalo's young receivers. The Bills took Robert Woods 41st overall and Marquise Goodwin 78th overall in the draft, and both have enjoyed strong training camps thus far.
"I look at it as an opportunity to get those younger guys more reps," Marrone said.
Former Kentucky standout Danny Trevathan, who had 30 tackles last season as a rookie, has had a good training camp so far and could be in line for playing time during his second season with the Denver Broncos.
"Especially in coverage, he's made huge strides from year one to year two," linebacker Von Miller said. "I think he's poised to have a great season this year."
Fellow former Kentucky Wildcat Wesley Woodyard saw this improvement back in mini-camp, DenverBroncos.com reported.
"Danny's going to be a great player," Woodyard said in April. "I feel like he has a big role coming up this year, and he's going to be one of the guys that I'm looking forward to being on the field, making plays right beside me and balling and having fun."
Not only has Trevathan shown some improvement in his coverage skills, he's been playing with a lot of physicality in training camp.
He laid one of the biggest hits of the day on Thursday when he popped Kemonte' Bateman after the rookie hauled in a catch.
"It makes practice more fun for me," Trevathan said about being physical. "It makes it more aggressive and it makes it more game-like. You know the guys on the field but you've got an attitude towards them that you don't want them to make a play on you. You want to make a play on them."
Williams in line to start
The Carolina Panthers released veteran offensive lineman Geoff Hangartner on Thursday evening, paving the way for former Kentucky standout Garry Williams to take over as the starting right guard.
Panthers Coach Ron Rivera said after Thursday's practice the move was made so the team to could focus on developing its young guards — particularly Williams and rookie Edmund Kugbila.
"We have Kugbila who is in the wings and Garry Williams who has done a really nice job and has had a nice spring in OTAs," Rivera said. "We're excited about what Garry can bring to the table."
Rivera said the Panthers had planned on Williams being their starting guard in 2011 before he broke his ankle in the pre-season and was sidelined for the season.
"He seems to be back in shape playing the way he did when we thought he could be a starting guard," Rivera said of Williams, who has started 20 games in four seasons.
Cooper to get counseling
The Philadelphia Eagles excused Riley Cooper from all team activities on Friday after the wide receiver was caught on video making a racial slur. Cooper said the last few days have been incredibly difficult and he will step away to seek counseling.
"My actions were inexcusable," he said. "The more I think about what I did, the more disgusted I get. I keep trying to figure out how I could have said something so repulsive, and what I can do to make things better."
The Eagles did not set a timetable for Cooper's return.
Around the league
Bengals: Cincinnati signed defensive tackle Vaughn Meatoga, giving him a chance to show he can fit into their line rotation. Meatoga also was with the Bengals in the 2012 pre-season. He spent time on the practice squads at Oakland and Seattle last year.
Seahawks: Wide receiver Stephen Williams was flipped in midair by safety Winston Guy and landed hard on his back during Friday's practice. Williams was tended to for a few minutes and then had to be separated from going after Guy, who starred at Lexington Catholic and Kentucky.
49ers: San Francisco signed wide receivers Austin Collie and Lavelle Hawkins to one-year deals.