According to witnesses at the venue, Manson collapsed during the encore while performing "Beautiful People", though many were unsure if it was part of the show until medics arrived. The band continued, either unaware or unsure what to do.
Now TMZ says sources have told them Manson had been feeling ill all day, but wanted the show to go ahead.
"Problem is, when he hit the stage he started feeling worse, vomiting on stage several times before collapsing," say TMZ. "We're told he still feels 'drained' but he's focusing on recovery."
Manson last hit the headlines in December when his ear had been reattached after a bar fight where he was hit with a glass table. "I was the victor, but had to have 24 stitches to keep my ear from becoming Van Goth," he said at the time.
See grainy footage of Manson's collapse here. He's the pixel with a black hat:
Were you at the show? What did you see? Tell us about it in the comments.