West Coast Eagles small forward Liam Ryan is expected to be sidelined for "an extended period" after sustaining a freak ankle injury when he kicked the go-ahead fourth quarter goal against Geelong on the weekend.

Ryan has been an exciting addition to the Eagles this season, but his exciting play and ability to sneak in quick goals was his undoing in the Eagles match at Optus Stadium on Sunday.

The 21-year-old claims that he heard a "crack" as his foot made contact with the ball late in the final quarter of he Eagles 15-point win over the Cats.

“I felt a little crack on my ankle,” Ryan told The West Australian.

He remained in high spirits after confirming that his injury may well stall his explosive three-game run with the eagles.

"It’s alright, it is what it is, I’ve just got to put up with it now."

Eagles coach Adam Simpson isn't as optimistic to hear that his electric new forward won't be available for selection for quite some time

"Unfortunately he won't be available for some time," Eagles coach Adam Simpson told Channel Seven.

"Obviously when you hear something like that it's not going to be too good when you look at the scans.".

Simpson and the Eagles are still awaiting confirmation of whether Ryan's injury is bone or ligament related, with the medical team still reviewing the results of the scans he underwent yesterday.