Former England international footballer Ugo Ehiogu is being treated in hospital after a reported heart attack at Tottenham Hotspur's training ground.
Ehiogu, 44, works as the Premier League club's under-23s coach.
The former Aston Villa and Middlesbrough defender collapsed and was treated at the scene before being taken to hospital by ambulance, Spurs confirmed.
"Everyone at the club sends their best wishes to Ugo and his family," Tottenham added in a statement.
His wife and son are with him.
Ehiogu, who has been at Spurs since 2014, began his career as a trainee at West Bromwich Albion before moving to Aston Villa in 1991.
He went on to feature in more than 300 matches for Villa over a nine-year spell, winning the League Cup in 1996.
After joining Middlesbrough for a then club-record £8m fee later that year, he won the same trophy with the northeast club in 2004.
Capped four times by England, he also played for West Brom, Leeds, Rangers and Sheffield United before retiring in 2009.
Aston Villa paid tribute on Twitter, saying: "Get well soon, @UgoEhiogu! Everyone at #AVFC wishing you a speedy recovery."
Tottenham's arch-rivals, Arsenal, have also wished him well.