Fremantle have sacked both coach Ross Lyon and chief executive Steve Rosich in a bombshell double decision.
The Dockers' board informed Lyon, who had a year to go on his AFL coaching contract, of their decision on Tuesday morning.
The axings follow the club's failure to make the finals since 2015.
Assistant David Hale will take over in a caretaker-coach role for Fremantle's final game of the season - Sunday's clash with the Power at Adelaide Oval.
"Leadership change is necessary to begin the process of renewal and to set our course for the next 10 years," Dockers president Dale Alcock said.
"Fremantle had not made the finals for the past four years. This isn't acceptable to the board, the players, and most importantly to our supporters.
"We need high performance and consistency at all levels of the club, so we need to change and evolve.
"This leadership change is about transforming our whole club. We need to act now to ensure we are reinvigorated and re-energised for success."
Chief operating officer Graeme Parker will act as interim chief executive until a permanent replacement is identified.
Lyon was under huge pressure earlier this season when Fremantle posted five losses from six games between rounds 14-19.
But the veteran coach seemed to have revived his prospects after guiding Fremantle to an upset 34-point win over Geelong in round 20.
Both before and after that game, Rosich gave his assurances that Lyon would stay on as coach next year.
Lyon not so ‘unsackable’ after all
Losses to St Kilda and Essendon over the past fortnight killed off Fremantle's finals hopes, but the general consensus was Lyon had done enough to continue as coach in 2020.
Lyon effectively labelled himself as unsackable during a press conference on July 9.
"I can guarantee you I'll be around," Lyon said at the time.
"My performance dictates we'll be around. We're a rebuilding team."
Lyon guided Fremantle to finals action in his first four years at the club, including the 2013 grand-final loss to Hawthorn.
But the Dockers fell off a cliff at the end of 2015 and haven't made the finals since.
Rumours are rife that players including brothers Brad and Stephen Hill, Ed Langdon and Luke Ryan could leave the club.
Fremantle had made major improvements this season but it wasn't enough to save Lyon's job.
Injuries to key players Jesse Hogan, Alex Pearce, Matt Taberner and Stephen Hill hurt Fremantle's cause, but it was the team's continued poor skill errors that frustrated fans the most.
Lyon is the fourth coach to either be axed or depart this season, after Brad Scott (North Melbourne), Alan Richardson (St Kilda) and Brendon Bolton (Carlton).
Brett Ratten is expected to be offered the full-time role at St Kilda, but Scott could be in the mix to join Fremantle.
Other potential Dockers candidates could include Peter Sumich, Justin Longmuir, Michael Voss and even current Essendon coach John Worsfold.
Scott Burns, Robert Harvey, Matthew Nicks and Adam Kingsley could also throw their hat into the ring.
Lyon joined the Dockers in September 2011 amid controversy - he had just coached St Kilda to the finals and had a year to go on his contract with the Saints.
But Lyon enacted a get-out clause in his contract and joined Fremantle, who had axed Mark Harvey as their senior coach despite him also having a year to run on his Dockers contract.
Lyon left St Kilda with the best winning percentage of any other St Kilda coach and was the first person to coach the Saints to four consecutive finals series.
Ross Lyon on SEN last week: "Both parties, particularly on the surface, are fully committed to turning it around. “I feel like I’ve never coached better."— Sam Edmund (@SammyHeraldSun) August 20, 2019
Shock to Ross Lyon. We understand Fremantle facing potential payout about $600k as that was base pay of contract with potential to earn an extra $250k as incentives relating to finals— peter ryan (@petryan) August 20, 2019