West Coast premiership player Willie Rioli will miss the next five weeks due to bone stress in his left foot.

Rioli was initially a week-by-week proposition, although the Eagles have now put a timeframe on his recovery after suffering the injury at training a week before round one.

“Willie’s got some bone stress in his foot which has been problematic,” General manager of football Craig Vozzo told the club's website.

“It is resolving itself from a pain perspective, but it’s a really delicate one that we need to treat accordingly. We re-scanned it recently and the doctor’s advice is that we give it more time to settle.

“Willie will be doing some aerobic training and a lot of off-legs stuff. We’ll have a graduated build up from here, which is quite conservative given the nature of the injury.”

Premiership teammate Liam Duggan will also miss this weekend's grand final rematch with Collingwood, although according to Vozzo, he should return the following week for the derby.

“Duggo suffered an MCL strain of his knee. He played out the game really strongly, but unfortunately coming into Sunday there was a bit of swelling and it probably hasn’t settled as quickly as we liked,” Vozzo told westcoasteagles.com.au.

“He’ll need to miss a week this week and hopefully we can fast-track him from there.”