Gallagher should be back to smashing watermelons in no time.

After running tests, doctors concluded that a heart attack caused the 64-year-old comedian's collapse last night while he was onstage at Whiskey Bone's Roadhouse in Rochester, Minn.

Gallagher's manager, Craig Marquado, called it a minor heart attack and said the funnyman, whose full name is Leo Anthony Gallagher, will spend at least one more night recuperating in the hospital before he's allowed to go home.

Witnesses said that Gallagher had complained of pain in his left arm and shortness of breath, both common indicators of a heart attack.