DENVER -- Denver Broncos head coach John Fox will undergo heart surgery early this week, a team spokesman said Saturday, after Fox was taken to a hospital after feeling "light-headed."
The surgery will require Fox to take a leave of absence from coaching the team. It's not yet known how long Fox will be away. The club was in negotiations with defensive coordinator Jack Del Rio to take over as head coach in Fox's absence, the Denver Post reported.
Fox was advised by doctors months ago that a defective aortic valve would require a replacement following the 2013 season, said team spokesman Patrick Smyth. Fox had a preoperative appointment on Thursday and his doctor said Fox should get medical help immediately if he felt any discomfort.
"On Saturday, Coach Fox began feeling light-headed while golfing with friends. He was taken to a hospital, where testing revealed he needed to have this procedure as soon as possible," Smyth said.
Fox will take a leave of absence from coaching for the next few weeks, Smyth said. The club has not yet announced who will serve a head coach in the interim.
"Our focus at this time is Coach Fox's health and well-being," Smyth said. "We extend our thoughts and well-wishes to him for a full and speedy recovery."
In a statement Fox thanked fans for their support.
"Although I am disappointed I must take some time away from the team to attend to this pre-existing health condition, I understand that it's the right thing to do. I have great confidence in our coaches and players, who are fully committed to our goals," Fox said. "I look forward to returning to coaching as soon as possible."
Earlier Saturday ESPN NFL reporter Adam Schefter reported Fox might have had a heart attack, however Smyth said that was not true.
Fox, 58, is in his third season with the Broncos after spending nine years as head coach of the Carolina Panthers.
The Broncos are 7-1, second in the AFC West to the Kansas City Chiefs. Denver next plays at the San Diego Chargers on Nov. 10.