Florida State athletic department spokesman Chuck Walsh says Mike Cofer, a former Pro Bowl linebacker with the NFL's Detroit Lions, had been suffering from a long illness.
Phil Cofer's father had suffered from an uncommon disease that affects organs and tissue.
Walsh says Cofer received the phone call notifying him of his father's death during the open locker room period after the win in the first round of the NCAA tournament and broke down into tears. He did not discuss it with the media. Florida State head coach Leonard Hamilton was not aware of the news when he spoke with reporters after the game.
Cofer missed Thursday's game with a right foot injury. He did not dress and his foot was in a boot. A Florida State official told ESPN it was "swollen" and started to affect him last week.
Cofer has averaged 7.4 points in 26.1 minutes per game this season. Last season, he led the Seminoles in scoring with 12.8 points per game.
Mike Cofer played for the Lions from 1983 to 1992. The Lions drafted him in the third round out of Tennessee.
The Associated Press contributed to this report.