A naive, 20-year-old Jagger was asked to help calm Brown down after he learned he wouldn't be headlining a T.A.M.I. Show special in the 1960s, and the Brit jumped at the chance to meet one of his heroes.
But Brown wasn't in the mood to meet fans.
Jagger tells Wenn, "James Brown was definitely the star but there were many others... like Marvin Gaye... and James was a bit annoyed as not being the last on the show.
"As I was the only one who had met him before, briefly, the producers of the show decided I was the fall guy. I was, like, 20, and they were like, 'You go and talk to him'.
"When you're 20 you go, 'Sure, I'll do it,' and of course that didn't work out well... He did this amazing performance and we (Rolling Stones) went on after. We had to work really hard, and maybe it was a better show because of that."
Jagger is the producer of new film Get On Up, which features 42 star Chadwick Boseman as late soul man Brown.