The Broncos head coach is in his third season in Denver. Denver Broncos head coach John Fox has been admitted to a hospital with a suspected heart attack, according to Adam Schefter of ESPN. Fox, in his third season as the head coach of the Broncos, has been coaching in the NFL since 1989. The former San Diego State player became a head coach in 2002 when he was given the reigns of the Carolina Panthers. With two NFC Championship games and one Super Bowl appearance, Fox is easily the most successful coach in Panthers history.