Rioli officially put in his request on Tuesday in a move that did not sit well with the Eagles.
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After playing a key role in the club’s 2018 premiership, Rioli’s career almost came to an end 12 months later when he copped a two-year doping ban for tampering with a urine sample.
In 2021 he was also placed on a good behaviour bond after pleading guilty to the possession of cannabis.
Despite the indiscretions, the Eagles stood by Rioli and he returned to the AFL this year to play 13 games.
“We could not have done any more to support Junior since his infraction in 2019,” CEO Trevor Nisbett said.
“We facilitated his appeal and subsequent return to football, so this decision is bitterly disappointing.
“We will put that disappointment to one side now and work to arrange a suitable trade for a player who has high end talent, is a premiership player and is in the prime of his career, having played just 51 games of senior football.
“Junior has made his decision and while he has indicated Port is his preferred destination, we will work to get the best outcome for our club.”
Former Eagle and Hawthorn star Xavier Ellis slammed Rioli for abandoning the club that looked after him during the tumultuous period.
Ellis said Rioli owed it to West Coast “to stick it out” after he was paid for two years when serving a drug ban.
“Not many players owe football clubs anything. It’s a business deal. It is literally shake hands, I’ve performed my contract. Much deeper here…,” Ellis said on Triple M last week.
“I feel as though he’s been babied…he’s been well and truly overcared for.”
Rioli last week said he hoped his new deal at Port Adelaide can set himself up for life after dealing with loss of his father Willie Rioli Snr to a heart attack in July.
“If I could set myself up for the rest of my life, that’s all I want to do … I’ve been through too much in the last 18 months so I just want to make the most of being in the industry I am now,” he said.
“A lot of this has been weighed up since before I came back to footy.
“It’s kind of been planned with me and my dad, but it’s been a bit slow now that my dad’s not here.
“It’ll work itself out, but I’ve got no plans so far, just to go wherever my manager tells me to go.”
Rioli, 27, has played a total of 51 games and kicked 60 goals since bursting onto the scene in 2018.