The Denver Broncos have confirmed that Gary Kubiak is stepping down as head coach - less than a year after leading them to victory in Super Bowl 50.
It was reported following Sunday's 24-6 win over the Oakland Raiders that Kubiak had told his players he was leaving, and confirmation of the 55-year-old's departure was made official by Denver on Monday.
Kubiak, who has spent 22 years with the Broncos during his career including nine as a quarterback, said in a statement: "As I told our team last night, this is an extremely difficult decision to step down as head coach.
"I love to work and I love football, but ultimately the demands of the job are no longer a good fit for me.
"I gave everything I had to this team the last two seasons but this year, in particular, has been tough on me. As hard as it is to leave this position, I know that it's the best thing for myself, my family and the Denver Broncos.
"I'm not sure what my future holds, but I know that I'll always consider myself a Bronco."
Kubiak, who suffered a complex migraine on October 9 and previously collapsed during a match while in charge of the Houston Texans in 2013, was appointed Denver coach in January 2015 and led them to a 24-10 win over the Carolina Panthers in last February's Super Bowl.
This campaign has not gone so well, however, with Denver missing out on the post-season after winning nine of 16 matches.
Kubiak is the latest NFL coach to leave their post in recent weeks.
San Francisco fired both general manager Trent Baalke and coach Chip Kelly after the 49ers' 25-23 loss to the Seattle Seahawks, while San Diego Chargers coach Mike McCoy was also dismissed on Sunday evening following a 37-27 defeat to the Kansas City Chiefs as the traditional 'Black Monday' firing season kicked into gear early.
Those departures came after Jeff Fisher (Los Angeles Rams), Gus Bradley (Jacksonville Jaguars) and Rex Ryan (Buffalo Bills) were all fired in the past few weeks.