AUSTIN, Texas (AP) - NFL Hall of Famer Earl Campbell says he is undergoing nerve treatment after doctors ruled out concerns that he might have Lou Gehrig's disease.

The 57-year-old former Heisman Trophy winner on Tuesday compared the effects of the nerve problem to a robot that moves its right leg when instructed to move its left.

Tyler Campbell, clarifying his father's comments to reporters, said his dad would be in and out of Austin medical facilities this weekend for treatment and tests.

Campbell was among the NFL's great power backs know for barreling over tacklers in eight seasons. But his punishing running style cut short his career and left with him with a litany of chronic health problems.

Campbell underwent knee replacement surgery last year and still requires a walker to move around.

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