[Buffalo Bills players hold hands in prayer for Bills' Kevin Everett.]
A trainer attends to Kevin Everett after he showed no signs of consciousness following a helmet-to-helmet hit on Denver's Domenik Hixon at the start of the second half.
Everett is in the intensive care unit at Buffalo's Millard Fillmore Gates Hospital after a four-hour operation performed hours after he was hurt in a season-opening loss to Denver, Eric Armstead, a partner of the player's agent Brian Overstreet, told The Associated Press on Monday.
"He'll be sedated for the next 24 to 48 hours and we won't know more until then," Armstead said. "We were told by the doctors that the surgery went well."
According to ESPN's Chris Mortensen, doctors in Buffalo have told members of the Bills that bone chips were removed during surgery.
Everett's family members, including mother Patricia Dugas, were to arrive in Buffalo on Monday from their Houston home, Armstead said.
Overstreet told the AP late Sunday that his client had some "sparse movement."
"The next couple of days is going to be critical," said Overstreet, responding to a question about paralysis. "Our concern is for him to come out of this healthy and, hopefully, be able to walk again."
The team doctor, John Marzo, is expected to provide a medical update in the afternoon.
Bills general manager Marv Levy on Sunday night said doctors informed the team that it's too early to determine the severity of the injury and they will know more after monitoring the player overnight.
"Certainly, we feel the injury is serious, but I don't want to speculate, and that's what the doctors told us," Levy said. "They told us to wait to hear from them before making any speculative announcement."
Everett sustained what the team called a cervical spine injury when he ducked his head while driving in to tackle Denver's Domenik Hixon during the second half-opening kickoff. Everett dropped face first to the ground after his helmet hit Hixon high on the left shoulder and side of the helmet.
Replays showed the player twitching for a few seconds as he attempted to get up before falling back to the ground. Everett had his eyes open but showed no further signs of movement during the next 15 minutes as the team's medical staff and emergency personnel carefully placed him on a backboard and, with the player's head and body immobilized, loaded him into an ambulance at the Broncos 30.
I hope he's okay. This is so sad.