Los Angeles: An emotional Gary Kubiak stepped down as coach of the Denver Broncos on Monday because of health concerns, less than a year after he led the team to a Super Bowl crown.

The 55-year-old fought back tears as he told reporters he was “retiring from coaching” at a farewell press conference in Denver, hours after the club confirmed his departure in a statement.

“This decision is strictly my decision, based on what I’ve been through this year and how I’m feeling,” Kubiak said.

“I just feel like it’s time for me to do something different. Now, I’m retiring from coaching, I’m getting out of coaching, but I’ve got a lot to give and I’m going to find something else to do... but it’s time for me to step away from the coaching field.”

Kubiak said it wasn’t a specific medical problem that prompted his decision but rather a feeling that he couldn’t meet the demands of the job as he would like.

“I’ve always taken a lot of pride that I could coach the football team, be there for the players, be there for the coaches, be there for the organisation, do a game plan, call some plays on Sunday.

“I’ve always taken a lot of pride in the fact I could do all those things, but this year I haven’t been able to do that.

“It’s been tough and for the first time I’ve had to tell myself, ‘Hey, you can’t do that anymore.’”

Kubiak was hospitalised briefly in October and missed coaching one game with what doctors called a “complex migraine condition” characterised by extreme fatigue and weakness.

In 2013, while Kubiak was head coach of the Houston Texans, he collapsed during a game with what was diagnosed as a “mini stroke.”

Kubiak had told players and staff after Sunday’s season-ending 24-6 victory over the playoff-bound Oakland Raiders that he was giving up the job after two years with the team.

“Although we fell short of our goals this year, I’m proud of our teams these past two seasons. Helping to bring Mr. [Pat] Bowlen, his family and this organisation its third Super Bowl is something that will always be very special to me,” Kubiak said in a statement.

John Elway, a former Broncos star quarterback and now executive vice-president of football operations/general manager, was expected to begin searching for a replacement immediately.

Elway hired Kubiak — his backup in their playing days — as the 15th head coach in franchise history on January 19, 2015 and Kubiak helped the Broncos to the second-most wins in the NFL in his two seasons with a 24-11 (.686) record.

During the 2015 season, Kubiak became only the fourth head coach in NFL history to lead a team to a Super Bowl victory in his first year, the Broncos beating the Carolina Panthers 24-10 in Super Bowl 50 in February 2016.