The world of football is mourning former England defender Ugo Ehiogu who has died aged 44.
Ugo Ehiogu's former manager Steve McClaren has paid tribute to the "warrior" of a defender.
Ehiogu collapsed at Tottenham's training centre on Thursday after suffering a cardiac arrest.
Former England manager McClaren won the 2004 League Cup at Middlesbrough with Ehiogu, who also played for Aston Villa, West Brom, Rangers, Sheffield United and Leeds.
McClaren said: "I'm absolutely devastated to hear the sad news about Ugo. What a sad loss he will be to football and, of course, to his family.
"I only saw him a couple of months ago on a coaching course at St George's Park, looking fit and healthy as always.
"I remember Ugo as a gentle giant of a man off the field, but a real warrior on it. He was a leader and he was well on the way to becoming a very good coach."
Boro chairman Steve Gibson spoke of "a great man", telling mfc.co.uk: "I'm deeply shocked. Ugo was one of our heroes in Cardiff when the club won its only ever major trophy.
"Ugo and Gareth Southgate were the rock on which Steve McClaren brought the club its best period in its history."
Ehiogu's former Villa team-mates Paul Merson and Lee Hendrie both added their tributes.
A clearly emotional Merson told Sky Sports News: "He was a top player, a top bloke and a good friend as well. He was always winding me up."
Hendrie added: "Ugo was such a character. He has always been that bubbly character. He was just a great guy to have around."
Current Villa manager Steve Bruce also paid tribute to Ehiogu, describing the centre-back as a "bargain" signing by former Villa Park boss Ron Atkinson in 1991.
Bruce told a press conference ahead of Villa's derby against Birmingham on Sunday: "I played against him. Big Ron bought him for #45,000 - what a bargain. He was a great player."
Stoke manager Mark Hughes also played against Ehiogu and remembered what it was like to face the defender.
Hughes said: "He was a big strong guy, a big athlete, and you knew when you went up against him it was always going to be a difficult game."
Villa, for whom Ehiogu played more than 300 games, tweeted: "We will be holding a minute's applause before our derby with @BCFC...
"Both sets of players will wear black armbands as a mark of respect."
Middlesbrough, where Ehiogu played over 100 times, tweeted: "MFC are deeply saddened to learn of the tragic passing of our former player Ugo Ehiogu. Our thoughts go out to Ugo's friends and family."
West Brom, where Ehiogu began his career, tweeted: "The thoughts of everyone at #WBA are with the family and friends of Ugo Ehiogu, who started his career at The Hawthorns. Rest in peace."
Rangers said in a statement: "The 44-year-old Englishman joined the Light Blues when Walter Smith returned as manager in 2007 and made a huge impact in his short time in Glasgow - notably his winning goal at Celtic Park in the derby"
Ehiogu played four times for England and was also part of the coaching team for England Under-20s at the 2013 World Cup in Turkey.
Football Association chairman Greg Clarke said: "We're devastated to hear the news that Ugo Ehiogu has passed away. Our thoughts and sympathies are with all lucky enough to know him. He will be much missed by the game he served so well."
Professional Footballers' Association chief executive Gordon Taylor said: "Ugo was a giant of a man in stature and quality, a wonderful player and top-class coach who really cared about the game.
"Ugo was a most dedicated and influential member of our Black Coaches group and toured the West Indies with our PFA Legends team and was a brilliant ambassador for the game."
Ehiogu was studying for a League Managers' Association diploma in football management at the University of Liverpool and course director Professor Sue Bridgewater said: "We have been fortunate to spend a great deal of time with Ugo over the past year. A nicer and more genuinely lovely man you couldn't wish to meet.
"An up-and-coming coach and prospective football manager, he had such a bright future ahead of him."
Tottenham forward Shayon Harrison, who was coached by Ehiogu at the club, added his own tribute.
Harrison, who is on loan at Yeovil, wrote on Twitter: "One of the most genuine, and caring people I've ever met. An honour to have been taught by you, not only as a player, but as a person."