Alastair Clarkson, the most decorated AFL coach of the modern era, is on his way out of Hawthorn and rival clubs are set to come hard at the four-time premiership mentor.
Former Hawks champion Sam Mitchell will take over from Clarkson ahead of the 2023 season as part of a succession plan.
Clarkson, who led the club to the 2008 premiership, then the 2013-15 flag three-peat, will stand down after 18 seasons when his contract expires at the end of 2022.
The 53-year-old's staggered departure comes when Collingwood are searching for a coaching replacement for Nathan Buckley, who recently left the Magpies after almost 10 seasons in charge.
David Teague is contracted at Carlton for next season but a coaching icon like Clarkson soon becoming available could bring about change due to an underwhelming season forcing an external club review.
Mitchell showed interest in the vacant Collingwood job but informed the Magpies in recent days he would be pulling out of the interview process.
Clarkson, who has fielded countless rival offers during his career, remains unsure what the future holds for him but declared the "club was bigger than the individual".
"My time at Hawthorn, the end has got to come at some point," Clarkson said.
"My wife and I have been wrestling with this, not just in these last 18 months, but for a period of time.
"Whether we liked it or not, the Collingwood decision to part company with Nathan Buckley - it didn't implicate us directly but indirectly it did.
"One of the options (Mitchell) the club had in mind of who could possibly coach this club beyond me was sitting in the process of Collingwood.
"I said 'let's be man enough to have these tough conversations'.
"I've been man enough to have a lot of those tough conversations with people other than me being right in the hot seat, now was the time for me to be in the hot seat."
Hawthorn decided on the coaching handover at a board meeting two weeks ago but opted to hold off on the announcement until Tuesday as not to take away attention from Shaun Burgoyne's 400th game.
Clarkson broke the news to Hawks players on Tuesday morning before fronting a media briefing.
He considered it a honour to be mentioned in the same context as other Hawks coaching legends John Kennedy Sr and Allan Jeans.
Clarkson is the most experienced coach among the league's current crop, having been in charge for 383 games since 2005.
Mitchell, who is coaching Hawthorn's VFL affiliate Box Hill, has been given a three-year contract when he steps into the job.
The midfielder played 307 AFL games for Hawthorn, winning four premierships under Clarkson's tutelage.
He started his coaching apprenticeship at the Eagles, learning from Adam Simpson as West Coast won the 2018 premiership.
Mitchell was lured back to the Hawks by Clarkson as an assistant coach for the 2019 season.
Hawks president Jeff Kennett conceded tough decisions had to be made for the club's future.
"We believe we've got to put in place someone who's heading coaching that will lead us through the next decade," he said.
"The same way that when Alastair came here (at the end) 2004; we thought we'd get 10 years, we've got 18.
"There are not many people in leadership positions anywhere who have long periods of time at one particular place of employment."
ALASTAIR CLARKSON'S COACHING CAREER
Premierships: 2008, 2013, 2014, 2015
Winning percentage: 59