ORCHARD PARK, N.Y. (AP) -- Fred Jackson's season is in jeopardy after the Buffalo Bills running back sprained a ligament in his right knee.
A person familiar with the injury told The Associated Press on Monday that Jackson does not require surgery, but is projected to miss between two and four games. The Bills (5-8), who "host" Seattle (8-5) at Toronto on Sunday, have three games left and have all but mathematically been eliminated from playoff contention.
The person said Jackson was diagnosed with a Grade 2 MCL sprain, and spoke on the condition of anonymity because the team has not revealed the exact nature of the injury.
Coach Chan Gailey, speaking on his weekly show on Buffalo's WGR-Radio on Monday morning, would only characterize Jackson's injury as "not good." Gailey added that the player will miss a minimum of two to three weeks, but added he's not received the entire prognosis yet from team trainers.
Gailey is scheduled to address reporters later in the day.
Jackson was hurt a day earlier with about 5:30 left in a 15-12 loss to St. Louis. He was bursting up the middle when two Rams defenders sandwiched his right leg in making a tackle during a 2-yard run.
Jackson lay on the field for several minutes and was unable to put much weight on his right leg while being helped off to the sideline. With a towel draped over his head, Jackson was then carted off to the locker room.
The injury is the latest setback for Jackson this year, and is to the same knee he sprained in a season-opening 48-28 loss at the New York Jets. Jackson missed the next two games. He also missed a 19-14 win over Miami on Nov. 15 after sustaining a concussion a week earlier.
Jackson, who's led the team in rushing in each of the previous three years, has 437 yards rushing this season -- his fewest in five seasons. He has scored three touchdowns rushing, and also has 217 yards receiving and a touchdown.
Jackson, who signed a two-year, $9 million contract extension in May, still led the Bills with 934 yards rushing last year despite missing the final six games with a broken bone in his right leg.
His injury means the Bills will lean more on co-starter C.J. Spiller, who has 944 yards rushing and five touchdowns. The 2010 first-round draft pick is averaging 6.55 yards per carry, which is the NFL's second-best total through 13 games since 1960 for a player with a minimum of 130 attempts. Jim Brown averaged 6.61 yards per carry for the Cleveland Browns in 1963.
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