Lee was injured during a practice at Holuba Hall in front of several hundred high school coaches in town for Penn State's Coaches Clinic. The injury happened on a non-contact play, according to several sources.
Most of Penn State's spring practice sessions are not open to the media.
Lee was taken from the field on a cart. He will undergo more extensive testing Saturday to determine the exact nature of the injury, sources say.
The two-year starter was Penn State's second-leading tackler in 2007 and has been projected as a possible first-round pick in the 2009 NFL Draft.
He has a redshirt available.
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