Broncos coach Vic Fangio addressed the move in a statement:
"After a lot of consideration and discussion after the season, I determined that a change at offensive coordinator ultimately would be best for our team. We need to do everything we can to get better—in all areas—as we start working toward next year.
"Rich is a bright coach with a great future ahead of him. I appreciate all of his hard work and thank him for his contributions to the Broncos."
NFL Network's Tom Pelissero first reported the news.
The Broncos finished 26th in offensive efficiency in 2019, per Football Outsiders, which was Scangarello's first year on the job. Denver also averaged the fifth-fewest yards (298.6) and points (17.6).
9News' Mike Klis provided more information on Fangio's decision to jettison one of his top assistants:
"Fangio met with Scangarello as part of his coaching staff’s end-of-year evaluations a couple days after the Broncos’ season finale victory against the Raiders. Although Fangio told 9News the day after the season he didn’t anticipate making any staff changes, he was waffling on whether to retain Scangarello for a second year."
According to Klis, Fangio also indicated to Broncos players at the team's year-end meeting that "taking a significant step on offense" was required to return to the postseason.
There's no question the offense fell short of expectations. The acquisition of Joe Flacco in March placed a level of pressure on Scangarello to deliver immediate returns, and the offense's inability to move the ball played a role in a 7-9 finish.
Still, firing Scangarello is a surprise since the unit appeared to be turning a corner once Drew Lock took over as quarterback. Lock finished with 1,020 passing yards and seven touchdowns in Denver's final five games.
The Broncos went 4-1 over that stretch, and Scangarello seemed to tailor the offense to Lock's strengths.
Jason La Canfora of CBS Sports reported in November that Fangio "has had issues with offensive assistants."
"Lines of communication have been strained, and Fangio has been quick to dispute play calls and come across as overbearing on the headsets, sources said, which has created issues in-game and otherwise," La Canfora wrote.
Fangio denied the report at the time.
NFL Network's Ian Rapoport speculated Fangio will look to "an experienced play-caller" to replace Scangarello, who had been the San Francisco 49ers' quarterbacks coach for two years prior to his move to Denver.
Furthering Lock's development will likely be one of Fangio's top priorities in his search for a new offensive coordinator.