Fremantle have confirmed that defender Alex Pearce has sustained a left knee injury during Saturday's clash against Melbourne at the MCG.

Playing as a makeshift forward, Pearce come off early in the second term after a marking contest. He was replaced by medical sub Stefan Giro.

Pearce has endured two long stints on the sidelines due to leg fractures, unrelated to the injury sustained in the game.

Fremantle will provide an update on the 25-year-old after he has had scans.