Gary Kubiak was expected to return to the sidelines as the Denver Broncos' offensive coordinator under new head coach Vic Fangio, but that will no longer happen, according to ESPN's Adam Schefter.

Kubiak and the Broncos met extensively and ultimately determined that they have different views on how the offense should be staffed and run, according to Schefter. This is a big surprise, not only because Kubiak is tight with Broncos GM John Elway, but he was expected to be a big resource for Fangio, the 60-year-old rookie head coach.

It's unclear whether Kubiak could return to coaching with another club in 2019, but the Broncos now have a big void to fill and at least some uncertainty as to how they'll do so. 9News' Mike Klis reports that Mike Munchak, the Steelers' offensive line coach who was the other finalist alongside Fangio to take over in Denver, still could be in the team's plans, but likely as the O-line coach, not coordinator.

Kubiak, who guided the Broncos to a Super Bowl 50 victory following the 2015 season before retiring the following year, spent last season in Denver's personnel department. But the former head coach was expected to be a key sounding board for Fangio, not unlike the role in which Fangio served under Bears rookie head coach Matt Nagy last season. Part of what made Nagy's maiden voyage so successful was his confidence in essentially setting and forgetting the 'D,' in the trusted hands of Fangio, to focus on the offense. Kubiak has vast experience both as a head coach and coordinator; is it possible he didn't like being passed over for Fangio?

Whether the Broncos can find someone else whom Fangio can trust to take the reins of the offense while he puts much of his attention on defense remains to be seen. A Pro Football Talk report prior to Fangio's hiring suggested that he was so determined to secure his first head-coaching opportunity that he would allow Elway to choose his staff. Will that now change? Will Elway, whose hands were all over Vance Joseph's staff, have a good contingency plan in place? It doesn't reflect well right now on the Hall of Fame quarterback and football czar, to be sure.

That unique arrangement with Elway had already to some questions regarding Fangio's fit in Denver, and the abrupt news of Kubiak's exit will only create more. It's easy to envision the Broncos' defense not only remaining the team's strength but improving under Fangio.

But the biggest issue facing the organization for several years has been behind center, where Case Keenum isn't more than a bridge guy and Kubiak was expected to work closely with him and whomever Elway potentially tabs as Keenum's heir. That plan apparently is no longer, and what looked like an excellent, off-the-beaten-path hire in Fangio suddenly comes with an asterisk.