Geelong half-forward Paul Chapman has been ruled out of Friday night's AFL preliminary final against the Western Bulldogs at the MCG.

Chapman tested his injured hamstring at Tuesday night's training session, and afterwards the Cats decided not to risk him in such an important game.

Cats coach Mark Thompson said on Monday he was not prepared to take players into the grand final decider who were still under an injury cloud, or who could be out of action early in the game.

Chapman injured his hamstring early in the qualifying final win over St Kilda and did not return after half-time.

Geelong say he will be sidelined for one week, which means he could return to the side for the grand final, provided the Cats beat the Bulldogs.

Brought to you by AAP © 2024 AAP