Richardson has knee injury, won't do on-field drills at combine

INDIANAPOLIS -- Trent Richardson will not participate in on-field drills at this week's NFL Scouting Combine because of a minor knee injury, a league source said Wednesday.

Richardson, the former Alabama star who's considered the top running back available in this year's NFL draft, suffered a minor injury in a practice leading up to last month's BCS national championship game, the source said, and had a "minor scope" about three weeks ago to alleviate his discomfort.

Richardson has made good progress since then, but as a precaution, he'll limit his activity at the combine. He's expected to be able to participate in all on-field testing at Alabama's March 7 pro day.

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