Kevin Kolb exited the Bills' preseason game with the Redskins on Saturday after getting kneed in the back of the head and was later said to have concussion-like symptoms.
One day later, on Sunday, a scary report from Tim Graham of the Buffalo News, via CBS Sports, is calling Kolb's NFL future in question.
Graham tweeted Sunday: "Source tells me Bills concerned Kevin Kolb's concussion may be career-ending and they're proceeding with that in mind.
"At least 3rd career concussion for Kevin Kolb. Hit didn't look serious, but source tells me response in locker room was disconcerting."
Kolb's first concussion came with the Eagles in Week 1 of the 2010 season, when he was tracked down by the Packers' Clay Matthews and slammed to the turf. Kolb would go on to lose his starting job to Michael Vick and was traded to the Arizona Cardinals the following offseason.
The Bills signed quarterback Matt Leinart on Sunday to account for Kolb's absence.
Giants: Stevie Brown done for season
EAST RUTHERFORD, N.J. -- New York Giants free safety Stevie Brown will miss the regular season with a torn anterior cruciate ligament in his left knee that he hurt in Saturday's preseason overtime loss to the Jets.
The 27-year-old Brown, who led the Giants with eight interceptions last season, was placed on injured reserve on Sunday.
"I feel badly for him," coach Tom Coughlin said in a conference call.
"He played well for us last year and prepared himself well for this season. We're definitely going to miss him. We'll continue, because that's what we do."
For now, it leaves the Giants without the starting safeties from a year ago, with strong safety Antrel Rolle still out with a sprained ankle (see full story).
Ravens: TE Shiancoe released
OWINGS MILLS, Md. -- Tight end Visanthe Shiancoe has been cut by the Baltimore Ravens, less than one month after joining the team as a free agent.
Shiancoe signed on July 28 after the Ravens lost tight end Dennis Pitta with a dislocated and fractured hip. The 33-year-old Shiancoe caught five passes in the preseason.
The addition of free agent Dallas Clark earlier this month made Shiancoe expendable.
Other cuts Sunday included offensive linemen Ramon Harewood and Jack Cornell; wide receivers Tommy Streeter, Rashaad Carter and Gerrard Sheppard; linebackers Bryan Hall and Meshak Williams and cornerback Mo Lee.
Linebacker Adrian Hamilton was placed on injured reserve.
The Ravens also signed quarterback Dayne Crist, who will serve as a backup in the preseason finale because second-stringer Tyrod Taylor has been undergoing concussion tests (see full story).
Steelers: Jones released from hospital
PITTSBURGH -- Steelers rookie linebacker Jarvis Jones has been released from the hospital after being treated for a chest injury.
The team said Sunday that tests were negative, but did not say what tests the first-round pick from Georgia underwent or whether he'll play in the preseason finale Thursday at Carolina.
Jones was hurt when he fell on the ball at the end of a third-quarter interception that was overturned against the Kansas Chiefs. He was on the turf for several minutes but walked off on his own power. He was wheeled out of Heinz Field on a stretcher late Saturday night.
Pittsburgh opens the season Sept. 8 at home against Tennessee. Jones has been sharing time with Jason Worilds at right outside linebacker (see full story).
Colts: LB Sidbury placed on IR
INDIANAPOLIS -- Indianapolis placed linebacker Lawrence Sidbury on injured reserve and waived 11 other players Sunday.
Indy has 78 players on the roster and must get to 75 by Tuesday.
Sidbury was signed in March as an unrestricted free agent and was supposed to help Indy on special teams and add depth at linebacker. He injured his shoulder last week against the Giants and sought a second opinion this week.
The Colts waived cornerbacks Johnny Adams and Allen Chapman, offensive linemen Danous Estenor and Rick Schmeig, defensive tackle Kellen Heard, punter-kicker Brandon McManus, running back Davin Meggett, linebacker C.O. Prime and safety Ashante Williams. Receiver Maurice Williams was waived with an injury settlement. Cornerback Teddy Williams was waived-injured and will revert to Indy's injured reserve if he clears waivers (see full story).
Bears: S Zbikowski, DE Moore released
LAKE FOREST, Ill. -- The Chicago Bears have released veteran safety Tom Zbikowski and defensive end Kyle Moore, along with 12 other players.
A Notre Dame product and a third-round pick by Baltimore in the 2008 draft, Zbikowski has appeared in 64 games with 25 starts over five seasons with the Ravens from 2008 to 2011 and Indianapolis in 2012.
Moore spent his first two seasons with Tampa Bay and the past two with Buffalo, making seven starts last year.
The moves were announced on Sunday. The Bears also released receiver Devin Aromashodu, running back Curtis Brinkley, defensive tackle Eric Foster, offensive tackle A.J. Lindeman, center P.J. Lonergan, safety Derrick Martin, tight end Gabe Miller, tight end Leonard Pope, defensive tackle Brent Russell, linebacker Patrick Trahan, punter Tress Way and linebacker Lawrence Wilson (see full story).