The 28-year-old had been on compassionate leave since early June, travelling with his family to home town Darwin to attend to personal matters.
Rioli was contracted to the Hawks until the end of the 2020 season but told his teammates of his decision to walk away from the game this morning.
“The decision to retire from football is something that I have thought long and hard about over the past 12 months,” Rioli said via a club statement.
“I’ve weighed everything up and I am confident the decision I’ve made is the right one for me and my family.
“Football has been my life but it’s always been difficult being away from home. Now is the right time to go home and spend more time with friends and family.
“I love the Hawthorn Football Club and I cannot thank them enough for the opportunities they’ve given me and the way they’ve embraced me and my family over the past 11 years.
“I can walk away from the game having achieved everything I could have ever dreamed of and I’m forever grateful for the opportunities I have received.
“I’d like to thank the Hawthorn fans for all their support over the years, it has been an honour to play in front of you each week.”
Rioli’s last AFL match was against Melbourne in round four.
The sublimely talented forward struggled with knee injuries over the past two seasons, which restricted him to four matches this campaign and seven last year.
He made 189 senior appearances for the Hawks, including the 2008, 2013, 2014 and 2015 grand final wins.
He won the Norm Smith Medal for his part in the 2015 grand final win over West Coast and was an All-Australian on three occasions.
“Cyril has been an outstanding servant of this football club for a long period of time and there have been very few players that have brought as much excitement to the game,” coach Alastair Clarkson said.
“His ability to influence a contest with a minimal amount of disposals is like no player I have ever seen and that’s why the whole footy world loves watching him play.
“Cyril came into our club as an 18-year-old kid and leaves an integral part of the fabric of the brown and gold family and the history of our game.
“I’d like to thank Cyril, Shannyn and the broader Rioli and Long families for their outstanding contribution to our club and wish them all the best for the next chapter of their lives.”
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