I guess this explains why you never heard anything about Walker
Junior defensive end Walker Ashburn had to retire from football, Pelini said, because of concussions. Ashburn had not been an on-field factor for his first three years at NU. Because the retirement occurred after July 1, Ashburn will not go on medical redshirt until after the season. It means, effectively, that one less walk-on can earn a scholarship during the season.