The West Coast Eagles have suffered a hammer blow a month out from the AFL season, with news fullback Eric Mackenzie has ruptured his anterior cruciate ligament.

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Mackenzie landed awkwardly on his right knee during West Coast’s NAB Challenge match against Carlton in Mandurah on Friday night.

Scans on Saturday confirmed the worst possible news for the 26-year-old, who is the Eagles’ reigning club champion.

Mackenzie has played 121 games for West Coast since being taken with pick 29 in the 2006 National Draft.

He was unlucky to miss out on All-Australian selection after a stellar season in 2014, and he beat out Brownlow Medallist Matt Priddis to take out the John Worsfold Medal for the Eagles’ fairest and best.

The club said he will have surgery on the joint next week when the swelling subsides.