The 58-year-old Fox will undergo aortic valve replacement surgery early next week at a hospital in Charlotte, N.C.
The Broncos did not immediately name an interim head coach.
Fox had been told earlier about his heart condition and was hoping to put off the operation until February. As part of his trip to North Carolina over the Broncos’ bye week, he met with his cardiologist and was told to seek medical attention immediately if he felt any discomfort.
On Saturday, Fox became dizzy playing golf near his offseason home and was taken to a hospital, where tests revealed he couldn’t wait any longer to have the surgery.
At 7-1, the Broncos trail the Kansas City Chiefs (8-0) in their division, but they’re widely considered Super Bowl favorites in the AFC with a high-octane offense led by Peyton Manning and a star-studded defense that recently was bolstered by the return of All-Pro linebacker Von Miller from a suspension.
Their next game is Nov. 10 against AFC West foe San Diego.
Although it hasn’t been determined who will serve as interim head coach during Fox’s absence, defensive coordinator Jack Del Rio is a logical choice because he spent nine seasons as the Jacksonville Jaguars’ head coach before joining Fox’s staff.
RECORD-MATCHING DAY: Philadelphia quarterback Nick Foles tied an NFL record with seven touchdown passes in the Eagles’ 49-20 victory over the Oakland Raiders.
Foles’ 5-yard touchdown throw to Riley Cooper, the wide receiver’s third scoring catch of the game, tied the record shared by Peyton Manning, Joe Kapp, Y.A. Tittle, George Blanda, Adrian Burk and Sid Luckman.
DOLPHINS: The team and the NFL are probing allegations of player misconduct made Sunday by representatives of Jonathan Martin, the second-year lineman who has left the team to receive help for emotional issues.
Martin left the Dolphins on Oct. 28 in a way that raised questions about the role teasing from teammates played in his sudden departure. It’s unclear whether or when Martin is expected back.
RAIDERS: Quarterback Terrelle Pryor was taken out of Oakland’s loss to Philadelphia midway through the fourth quarter with what was described as a knee injury.
He was replaced by undrafted rookie Matt McGloin.
Pryor had thrown for 288 yards on 22-of-41 passing with two interceptions while also rushing for 94 yards on 10 carries.
TEXANS: Running back Arian Foster played only one series against the Indianapolis Colts on Sunday night before leaving the game with a back injury.
He didn’t carry the ball at all.
Foster didn’t play in the preseason due to a back strain. He also had a calf injury that caused him to begin training camp on the physically unable to perform list.
Foster had actually been listed as questionable for Sunday night’s game due to a hamstring injury suffered two weeks ago against the Kansas City Chiefs, but was ruled well enough to play.