MELBOURNE, AUSTRALIA - SEPTEMBER 29: Willie Rioli of the Eagles holds up the Premiership Trophy after the Eagles won the 2018 AFL Grand Final match between the Collingwood Magpies and the West Coast Eagles at Melbourne Cricket Ground on September 29, 2018 in Melbourne, Australia. (Photo by Quinn Rooney/Getty Images)

Premiership Eagle Willie Rioli has been suspended indefinitely after returning an adverse urine sample on an ASADA drug test.

ASADA has alleged that Rioli substituted a urine sample taken two days after the Eagles' round 22 match against Richmond.

The 24-year old is facing a maximum four-year ban.

He has been withdrawn from the side's qualifying final clash against Geelong on Friday night at the MCG.

“It is asserted that Rioli’s ‘A Sample’ returned an adverse analytical finding for urine substitution, which is a prohibited method under the code,” AFL general counsel Andrew Dillon said.

“ASADA informed the AFL yesterday of the results of the testing of the sample, and Rioli was was formally notified late last night when he came to Melbourne.

“Under the code, ASADA conducts testing for the AFL as part of a comprehensive anti doping program, designed to protect the integrity of the AFL competition.

“The provisional suspension is effective immediately. Rioli will not be eligible to compete in AFL competitions or any WADA compliant sport, including the WAFL, while provisionally suspended. He’ll be able to train prior to the final determination of the asserted violation.

“Rioli has been withdrawn from the West Coast Eagles team that will play Geelong tomorrow night. It is important that Rioli is provided a fair process.”

West Coast said in a statement: "The Eagles have been made aware that Willie Rioli is the subject of an ASADA and AFL investigation.

"The club is extremely disappointed that one of our players has been provisionally suspended while a matter is being investigated and it will comply fully and openly with ASADA and the AFL through the process.

"The club is fully committed to supporting Willie during what is a personally distressing time.

"Our primary concern is Willie's health and welfare.

"As this is an ongoing investigation the club, its staff and players can make no further comment until the investigation is completed.

"The West Coast Eagles fully supports the AFL and ASADA in its ideal of our game being drug free."

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