Bob Hartley, who failed to make the playoffs in three of his four seasons in Calgary, was fired by the Flames on Tuesday, the team announced.
Hartley, who was named the NHL's coach of the year after guiding Calgary to the Western Conference semifinals last season, did not qualify for the playoffs this year as the Flames went 35-40-7 and finished fifth in the Pacific Division.
Sources told ESPN's Pierre LeBrun that Flames management did a thorough review after the season and decided it was best not to retain Hartley, who had one more season remaining on his contract.
Hartley won a Stanley Cup with the Colorado Avalanche in 2001. In 2014-15, he led the Flames to a 45-30-7 record and third place in the Pacific Division, but there was no sign of that team this season behind Johnny Gaudreau and Mark Giordano. In February, Calgary dealt forward Jiri Hudler to Florida for draft picks and sent winger David Jones to Minnesota for goalie Niklas Backstrom and a sixth-round pick.
The Flames also fired associate coach Jacques Cloutier.
After surprising many by making the playoffs in 2014-15 and beating Vancouver in the first round, Calgary finished 26th overall this season. The Flames' 77 points were 20 fewer than a year ago.
The problems came despite high-profile offseason additions. The Flames acquired defenseman Dougie Hamilton from the Boston Bruins at the draft, Michael Frolik signed as a free agent, and Sam Bennett had a breakout rookie season.
But Calgary stumbled early, losing its season opener to Vancouver en route to a 2-8-1 start. The Flames weren't able to recover. Unlike last season, they rarely rallied to wins in the third period.
The team began the season with three goalies on one-way contracts. Karri Ramo and Joni Ortio both were waived at different times and sent to the minors. Veteran Jonas Hiller also struggled, his .879 save percentage the worst in the NHL in the last decade with a 25-game minimum.
General manager Brad Treliving has said Hiller will not be back. The door is still open for Ramo, who suffered a season-ending knee injury in February and Ortio, who played well down the stretch.
Hartley, who went 134-135-24 during his time with the Flames, has coached parts of 14 NHL seasons, including stints with the Atlanta Thrashers (2002-08) and the Avalanche (1998-2003).
The Associated Press contributed to this report.