Earlier this month, cornerback Antone Exum announced he would return to Virginia Tech next season rather than enter the NFL Draft.
But now his 2013 season is in jeopardy after the school announced on Sunday that he has torn his anterior-cruciate ligament and his lateral meniscus in his right leg.
A date for surgery has not been set, but it could be performed this week.
The school estimates that recovery time is between six and nine months, which makes it possible that Exum will be ready for the start of next season if he recovers quickly.
The school did not specify how Exum sustained the injury, although CollegeFootballTalk.com reported there's speculation it occurred during a pickup basketball game.
Exum, who will be a senior next season, was a second-team all-Atlantic Coast Conference selection this past season. He had five interceptions and 16 pass breakups in 2012.