He started working with the Rolling Stones in 1969 and continued until he was forced to stand down due to ill health in October - although at the time the Stones reported: "He's under doctor's orders to take it easy for the next month and hopes to see everyone soon."

Keys, a Texan, became a full-time musician at the age of 15 and worked with Buddy Holly and Bobby Vee. He first met Mick Jagger and co in 1964 although he didn't play with them until five years later when he appeared on Let It Bleed. He played on every subsequent record until 1974's It's Only Rock And Roll, then returned from 1980's Emotional Rescue to 2005's A Bigger Bang.