West Coast fear Liam Ryan's ankle injury means the outstanding youngster will have a long spell out of the AFL.
Ryan heard a crack when he soccered through the goal that put the Eagles ahead in Sunday's tight win over Geelong.
It was typical of the impact the 21-year-old forward has had since he made his debut in round one.
He has lit up the league with goal and mark of the year contenders.
"It's not looking great. I think he'll probably have an extended period off football," Eagles coach Adam Simpson told the Seven Network on Monday.
"(It's) really unfortunate because he was producing some really good highlight reels for us and kicking some goals.
"Unfortunately he won't be available for some time."
West Coast remain unsure whether Ryan has suffered ligament or bone damage.
Ryan has kicked seven goals so far this season.
Simpson said star key forward Josh Kennedy would return in the next week or two from off-season surgery.
