Luke Bryan -- Stage Collapses -- Crew Injured

Several stage hands were rushed to the hospital Thursday night after Luke Bryan's Ohio State concert ... after the singer's stage collapsed, TMZ has learned.

Law enforcement sources tell us ... a forklift crashed into a portion of the stage during take down, and it crumpled.

We're told 4 people -- including guys from Luke's crew as well as arena staff -- were taken to a nearby hospital with injuries. Their current medical status is unclear.

Luke's next concert -- scheduled for tonight in Lexington, KY -- has been pushed to February because of obvious stage problems.

Luke called into a Lexington radio station -- the Officer Don & DeAnn show -- to talk about the accident and the postponed concert.