Nazareth had to halt a gig in Canada on Tuesday (09Jul13) after frontman Dan Mccafferty collapsed just seconds into the band's first number.
The Scottish rockers had just opened their set at the Cranbrook Curling Centre in British Columbia when the singer passed out and was dragged offstage to receive medical attention.
The group had to abandon the show.
Concert promoter Isaac Hockley reveals the 66 year old was having lung problems and struggling to get enough air, but he tells local publication Cranbrook Daily Townsman the star is now in a "stable" condition.
The fate of the band's current North American tour is currently unknown. There has been no update about the gigs or MCCafferty's condition on the band's official website.
The latest drama follows reports the veteran rockers were on the verge of splitting up - speculation founder member Pete Agnew has dismissed.
In a recent statement the bass player said, "This is, of course, a load of rubbish, and I don’t know where these clowns get their stories from."