Karageorge was last seen by his roomates when he left his Columbus, Ohio, apartment around 2 a.m. Wednesday while apparently upset, Sophia Karageorge told the newspaper.
According to the Columbus Dispatch, Kosta Karageorge's family and friends are planning to search for him on Friday.
An Ohio State spokesman confirmed that the 6-foot-5, 285-pound Karageorge has missed two team practices since he was last seen but declined further comment.
Karageorge left without his wallet, and his family is concerned that he might have become disoriented because he has a history of concussions, Sophia Karageorge said.
According to the missing persons report filed with police, Kosta Karageorge's mother said she received a text message from her son early Wednesday morning that said: "I am sorry if I am an embarrassment but these concussions have my head all [expletive] up.”
Kosta Karageorge, a senior, made the Buckeyes' roster as a walk-on this season. He's appeared in one game. He has been on Ohio State's wrestling team for the last three seasons.
Ohio State will play Michigan on Saturday.
The Associated Press contributed to this report.