(TMZ) - R&B singer Raz-B is currently on life support in a hospital in China... just one day after he was smashed in the face with a bottle at a nightclub, TMZ has learned. 

TMZ spoke to Raz's publicist, Toy Jones, who says, "He is in a coma and needs as many prayers as possible."

As previously reported, the 28-year-old was performing at a club in China on Thursday and was smashed in the face with a glass bottle while trying to break up a fight that erupted in the crowd. 

Raz received medical attention hours after the incident -- and underwent minor surgery to repair a gash in his lip. 

But the next day, sources close to Raz say he didn't wake up ... and Raz's backup dancer rushed him to a nearby hospital for treatment. 

Doctors tested for brain activity and determined the situation was dire. Sources say Raz is breathing from a ventilator... and has been slipping in and out of consciousness. 

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