Marc was diagnosed with throat cancer in 2001 when he was touring with Joe Brown and Marty Wilde. In 2008, he was told by his doctors that his cancer had gone into remission. In 2014 Mac stopped playing after 54 years due to his illness.

The drummer, who became a leading light in the Birmingham, England music scene in the late 1960s and 1970s, played with The Dangerfield Band, Warhorse (also featuring former Deep Purple bassist Nick Simper and future Yes keyboardist Rick Wakeman) and Gong.

It was followed by stints with The Greenie Allstars in the 80s, The Solid Gold gigs in the 90s and The Honeycombs after the millennium.

However, Mac passed up a chance to join Jimmy Page's band, then called The New Yardbirds. The drummer was a friend of Robert Plant, who approached him about coming with in a group he had just joined. As Mac recounted in Mick Wall's book, 'When Giants Walked the Earth - A Biography of Led Zeppelin':

"Robert [Plant] put it to me in a very kind of simplistic way. He just said, 'I'm doing these sessions with a guy called Jimmy Page, and we’re gonna get a band together and we're gonna call it the New Yardbirds — and we need a drummer.' That was like asking me if I was free. That's how we did it in Birmingham, you sounded people out first, you didn't just say, 'Do you want the job in the band?' But I just said, 'Well, I've got my own band, Rob, we've got our own deal.'"