Premiership West Coast Eagles star Junior Rioli has formally told his club he is seeking a trade to Port Adelaide.

Speculation had been rife Rioli would request the trade after the 27-year-old's interstate trip to meet with Port Adelaide last Monday.

The Eagles released a statement on Tuesday evening revealing the club's disappointment at the move.

That disappointment stems from the club's backing of Rioli through his two-year ban for substituting a urine sample ahead of the 2019 finals campaign.

"We could not have done any more to support Junior since his infraction in 2019," Eagles chief executive 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."

Nisbett said while Port was Rioli's preferred destination, the Eagles would work to get the best outcome for the club.

Rioli was drafted to the Eagles in 2016 and was a member of the 2018 premiership team.

He resumed this season after a two-year ban for substituting a urine sample ahead of the 2019 finals campaign.