Phil Collins says he considered quitting mid-performance during Led Zeppelin's underwhelming reunion show at Live Aid on July 13, 1985.

In fact, he tells Q, that he realized "this is a mistake" even as the set got underway. Collins was filling in, along with Tony Thompson of Chic, for the late John Bonham -- whose 1980 death had precipitated Led Zeppelin's breakup.

This initial reunion, however, had come after little rehearsal time, as Collins also performed earlier that day at the Live Aid event in London -- then caught a Concord to Philadelphia for the Zeppelin gig. Worse still, there were technical problems for Jimmy Page and vocal issues for Robert Plant.

“It was a disaster, really. Robert wasn’t match-fit with his voice and Jimmy was out of it, dribbling. It wasn’t my fault it was crap,” Collins says. “If I could have walked off, I would have. But then we’d all be talking about why Phil Collins walked off Live Aid -- so I just stuck it out."

Collins had happily collaborated on earlier Plant solo work, and admits he thought Live Aid would follow that template. Instead, he says "you could sense I wasn’t welcome" -- particularly, Collins adds, on the part of Page.

“I thought it was just going to be low-key and we’d all get together and have a play," Collins says. "But something happened between that conversation and the day -- it became a Led Zeppelin reunion. I turned up and I was a square peg in a round hole. Robert was happy to see me, but Jimmy wasn’t.”

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