Ugo Ehiogu's death at age of 44 prompted tributes from all over the football world as former team-mate Paul Merson broke down in tears and said "only the good die young".
Former England defender Ehiogu, who was Tottenham's Under-23s coach, collapsed at the club's training centre on Thursday after suffering a cardiac arrest.
Ex-clubs and team-mates have paid tribute to a "gentle giant", whose death was announced by Tottenham this morning.
"It is with immense sadness that we announce the passing of Ugo Ehiogu," the club said.
Ehiogu, who played for Aston Villa and Middlesbrough and was capped by England on four occasions, joined Spurs as a coach in 2014.
He played alongside Merson at Villa and the television pundit broke down on Sky Sports as he watched footage of his friend.
"Billy Joel sings that song, 'Only the good die young' and that is him," he said. "He was a top player, a top bloke and a good friend as well. I talked to him recently and he was always winding me up, telling me Tottenham had some good players coming through..."
Merson's tribute was cut short as he started to cry.
In announcing the death, Spurs' head of coaching and player development, John McDermott, said: "Words cannot express the sadness that we all feel at the club. Ugo's immense presence will be irreplaceable.
"Our heartfelt sympathies go out to his wife Gemma and his family."
Spurs also added their thanks to the North Middlesex University Hospital, Royal Brompton Hospital and Harefield Hospital, while the club's age-group fixtures have been cancelled this weekend. Spurs' first team play Chelsea in the FA Cup semi-finals on Saturday.
Lee Hendrie played with Ehiogu at Villa and then later in his career at Sheffield United.
"This is an absolute shock, to think this could happen to a man of his fitness and age. It is devastating, crazy," he told Sky Sports.
"He was such a character, bubbly and would help anyone. He was a great guy to have around and never had problems with anyone. He was a gentle giant."
Ehiogu's caring nature became further apparent from the final tweet sent from his Twitter account.
"Gave a homeless girl £10 last night in Dalston," he wrote on March 29. "She didn't ask or beg. Random impulsive act from me. Not gonna lie, felt good. #dosomethingkind."
Ehiogu began his career as a trainee at West Brom before he was taken to Villa by Ron Atkinson in 1991. He went on to feature in more than 300 matches for Villa and played in their FA Cup final defeat against Chelsea in 2000.
He won the League Cup with Villa in 1994 and 1996 and former team-mate Andy Townsend told Radio 5: "I remember the 3-0 win over Leeds (in 1996) and I looked at the pictures this morning. Ugo is in them celebrating.
"He was commanding and formidable in the air. He was a player that every team would have liked at the back."
Ehiogu joined Middlesbrough for a then club-record £8million fee later that year, and in 2001 he scored his only goal for England in Sven Goran-Eriksson's first game in charge, a 3-0 friendly victory against Spain.
The Football Association tweeted it was "devastated to hear the news" and further tributes from the governing body were expected, with England manager Gareth Southgate having played with Ehiogu for both Villa and Boro.
Villa released a statement expressing their sadness and added that there would be a minute's applause ahead of their derby with Birmingham on Sunday, with the teams wearing black armbands.
Boro owner Steve Gibson, who also saw Ehiogu lift the league cup for his club, said: "Ugo and Gareth Southgate were the rock on which Steve McClaren brought the club its best period in its history.
"He wasn't just a good footballer, he was a great man. It's so sudden and so shocking, my deepest sympathies go to his family and all who knew him.
"I would regularly bump into Ugo. Football is a small world and he was always warm, friendly and welcoming. All of Middlesbrough Football Club will miss him."
McClaren said: "He was a gentle giant of a man off the field but a real warrior on it."
Knee injuries plagued the final years of Ehiogu's career at the Riverside Stadium.
He joined Leeds on loan in 2006, and also had short spells with Rangers and Sheffield United before he retired from football in 2009.