Former England international and coach Don Howe has died aged 80, the Football Association has announced.
Howe represented West Brom and Arsenal as a full-back during his playing days and also worked at both at both clubs during an esteemed coaching career.
He was capped 23 times by England, playing in all of his country's matches at the 1958 World Cup and, in 2004, he was named as one of West Brom's 16 greatest players in a poll organised to mark the club's 125th anniversary celebrations.
Howe served as part of the backroom teams of former England manager Ron Greenwood, Bobby Robson and Terry Venables.
FA Chairman Greg Dyke said: "It is terribly sad news and our thoughts are with Don's family at this time.
"He is widely regarded as being in the vanguard of coaching in England, and I know that his loss will be keenly felt amongst the coaching fraternity in particular and not least by [England manager] Roy Hodgson, who was close to Don.
"He was a fine player - named as one of West Bromwich Albion's finest - and, of course, he went on to play an integral part in Arsenal's history as a coach and later as manager.
"For his country, he not only appeared in a World Cup, but he was instrumental in both Sir Bobby Robson's management team for Italia '90 and Euro '96 where he assisted Terry Venables."
Arsenal chairman Sir Chips Keswick said: "We were aware Don had been enduring a long battle with illness, but it was still a shock to learn the news about someone who was loved by so many people at the club, and who had such a remarkable influence as a player, coach and manager here.
"Don possessed a marvellous ability to get the very best out of players with his coaching techniques and provide them with the perfect preparation for matches. He was the very best at what he did - and he did it with us, at Arsenal, for decade after decade.
"He will be greatly missed by everyone who knew him and his name will live on in the history books as one of the most influential footballing figures in the history of the club."