Bills running back Fred Jackson is expected to miss the remainder of the 2012 season with a knee sprain, according to CBSSports.com’s Jason La Canfora via Twitter:

Bills RB Fred Jackson has a grade 2 sprain and not an MCL tear, but is expected to miss remainder of season. expected out a month—
Jason La Canfora (@JasonLaCanfora) December 10, 2012

Bills coach Chan Gailey said Jackson would miss just 2-3 weeks on a Monday morning radio show.

Jackson injured his knee in the fourth quarter of the Bills’ 15-12 loss to the Rams. It is Jackson’s second injury to the same knee this season.

Jackson was sidelined the last six games of 2011 with a broken leg, ending a streak of 61 consecutive games beginning in the 2007 season.

He is likely to finish 2012 with his lowest rushing totals since his rookie season, with 437 yards on 115 carries.

Michael Vick was one of three quarterbacks who suffered concussions on Sunday. The NFLPA is calling for independent doctors to assess hits to the head due to inconsistent adherence to concussion policy. (Elsa/Getty Images)

The NFL Players Association has asked the league to hire concussion specialists with no team affiliation to evaluate and treat players, according to ESPN’s Chris Mortensen:

NFLPA sources said the union wants the league to accept responsibility for creating a disciplined, prompt and safe environment for players who are injured during the course of a game. They said the union wants concussion specialists, paid not by the teams but by the league, to assume the duties of caring for players, in accordance with normal employer workplace oversight.

Several high-profile players suffered concussions on Sunday including quarterbacks Michael Vick, Jay Cutler and Alex Smith and running back Fred Jackson. Of the quarterbacks, only Vick was quickly taken out of the game; Cutler and Smith continued playing despite being shaken up before they were eventually taken out, according to NBC Sports.

The NFLPA has been frustrated by inconsistent adherence to concussion guidelines, and Sunday’s developments only exacerbated concerns. Independent doctors would be more likely to insist on checking players after hits and removing them immediately.

The Buffalo Bills might have lost more than just a Week 1 game to the New York Jets on Sunday. They are afraid wide receiver David Nelson tore his ACL, Pro Football Talk reported Sunday night via Twitter.

Bills specifically fear WR David Nelson has torn ACL, per league source.

— ProFootballTalk (@ProFootballTalk) September 9, 2012

The Bills fell to the Jets on Sunday, 48-28. They lost both Nelson and running back Fred Jackson to injuries. Nelson left the game in the fourth quarter, appearing to hurt himself while making a cut.

The Buffalo News’ Tim Graham reported that the prognosis looked a lot worse for Nelson than Jackson:

“Fred doesn’t look as bad as David,” Bills coach Chan Gailey said. “We don’t know how bad David is, but it doesn’t look good right now.”

Jackson’s injury is believed to be a sprain. There was no word on how bad Nelson’s knee was. They will be re-evaluated Monday after MRIs pinpoint the extent of their injuries.

Nelson was second on the Bills last season with 61 catches for 658 yards. The third-year receiver from Florida also caught five touchdown passes last year.

The Buffalo Bills want to give running back Fred Jackson a contract extension, according to the team’s official website.

“Fred and I have talked,” said Bills GM Buddy Nix. “We want to extend Fred. I’d like for Fred to finish his career as a Bill. He’s meant a lot to us. I’ve got great respect for him. We do want Fred back and we do intend to try to work out a deal with him. I’ve told him that. What we said is what we’re going to do.”

Jackson currently has one year remaining on a multi-year deal he signed with Buffalo in the 2009 offseason. He was just recently cleared to resume football related activities after a fractured fibular forced him to miss the final six games of what was going to be a break-out-year for the former undrafted free-agent.

Through the Bill’s first 10 games last season, Jackson had run for 934 yards on 170 carries, and had scored six touchdowns on the ground. He had also hauled in 39 passes for 442 yards.

Buffalo Bills star running back Fred Jackson will not play this Sunday against the New York Jets, according to the Associated Press.

Jackson, 30, was ruled out by Bills head coach Chan Gailey due to a nagging right-calf injury the tailback suffered in a loss to the Miami Dolphins last week. In just seven carries against Miami, Jackson gained 17 yards on the ground. He also caught five passes for 50 yards.

In 10 games this season the former undrafted free-agent has run for 934 yards and collected six touchdowns on the ground.