Buffalo Bills coach Doug Marrone says the injury is not serious and expects the quarterback to return to practice - and his competition with E.J. Manuel for the starting job - within days.
Kolb was hurt while going from one field to another with his offensive teammates. As he ran, Kolb slipped on a wet rubber mat and stumbled awkwardly at the Bills training camp facility in suburban Rochester on Saturday.
Though Kolb did not fall, he had trouble standing and put his arm around the shoulder of head trainer Bud Carpenter. Kolb then tossed down his helmet in frustration, before sitting down on the field.
Carpenter briefly examined Kolb's knee before escorting him to the locker room. Workers then began sweeping water off the mats, which were in a tunnel between fields. The mats provided little traction, especially for players wearing cleats.
Kolb is entering his seventh NFL season after signing a two-year contract with Buffalo in free agency in April. Kolb was counting on kick starting his career in Buffalo after injuries contributed to him losing the starting job in both Philadelphia and the past two seasons in Arizona.
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