Gallagher Collapses On Stage

3/11/2011 12:50 AM PST

Gallagher Collapses On Stage

Comedian Gallagher collapsed onto his back, clutching his chest during his performance tonight in Rochester, MN -- and TMZ has learned he was rushed to a hospital by ambulance.

Multiple witnesses tell TMZ Gallagher was doing his famous sledge-o-matic routine when he fell backwards onto the stage. We're told his eyes were closed and he was shaking.

Doctors -- who happened to be in the audience -- rushed on stage and straightened out Gallagher's arms ... and waited by his side until the ambulance arrived.

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