"He is in a coma and needs as many prayers as possible," the Cleveland native's spokesman, Toy Jones, told TMZ Friday.
The 28-year-old recording artist, whose real name is De'Mario Monte Thornton, was performing Thursday when he was hurt while trying to break up a fight in the audience, the celebrity news website said.
He had minor surgery to repair a gash in his lip and was released from the hospital.
However, he didn't wake up Friday morning and was taken back to the medical facility where he has been slipping in and out of consciousness, and breathing with the help of a ventilator, Jones told TMZ.
The report did not say if any arrests were made following the brawl. Also not mentioned was exactly where the altercation took place.