West Coast Eagles' forward Willie Rioli has been hit with a two-year suspension for substituting a urine sample during a drug test in 2019.

Rioli will be eligible to return to football for the West Coast Eagles this season, after the AFL confirmed the premiership player's suspension had been backdated.

Rioli was provisionally suspended during the 2019 AFL finals campaign after allegedly tampering with the sample, and tested positive to cannabis a fortnight later.

He was found guilty of three breaches of the AFL's anti-doping code, two relating to tampering with a urine sample and one for the use of cannabis.

The anti-doping tribunal determined the two-year suspension would begin from the date of his first sample on August 20, 2019, meaning he could be free to play in the Eagles' last home and away game in 2021.

He will be eligible to train with West Coast from June 20.

In a statement, the club said the tribunal took into account Rioli's personal circumstances, the fact he was not seeking to gain a competitive advantage, and that his breach was certain to be detected.

It said Rioli had also admitted to the violations.

Eagles look forward to Rioli's return

West Coast Eagles chief executive officer Trevor Nisbett said the club was pleased the matter was closed.

"We are pleased for Willie that this ordeal is now over and he has some clarity around his future," Mr Nisbett said.

"We look forward to him returning to the club and resuming what is an integral part of his life," he said.

"It has certainly been very challenging for all concerned and what this case has highlighted is the need to continually educate, and that the programs in place do not necessarily suit all players."

Rioli 'sorry for letting people down'

Rioli said it had been a difficult period and he was looking forward to playing football again.

"I am very relieved that this long process has now ended," he said in a statement.

"The stress of waiting for the outcome over a long period of time has been difficult for me and my family.

"I realise I have done wrong things and I have learnt from it.

"I am sorry for letting people down.

"I am looking forward to putting all this behind me and playing footy again soon."

The Eagles and the AFL have previously expressed frustration with how long the process has taken, with Rioli's wait for an outcome from the Australian Sports Anti-Doping Authority approaching a year and a half.

The AFL Players' Association (AFLPA) said it was "satisfied" with the final outcome and was delighted Rioli would have the opportunity to resume his AFL career in 2021.

But AFLPA said it was concerned about the length of time it took for an outcome, and implored Sports Integrity Australia (SIA) to conduct a review of its processes to remove unnecessary delays.

"The time it takes for an athlete to progress through this system places significant strain on their mental health and wellbeing, as well as that of their family," AFLPA said in a statement.

"Identifying ways to expedite the process and taking a more reasoned approach will also help to avoid the potential situation where an athlete is forced to serve a provisional suspension that is greater than that of the final decision of the tribunal."

It has been 18 months since the small forward last played at AFL level.

He has been spending time with his family in the Tiwi Islands while awaiting the final verdict.

Rioli, 25, had faced a maximum four-year ban.