Sydney Swans defender Aliir Aliir has been ruled out of Saturday’s premiership decider.

Aliir was unable to get through Sydney’s main training session on Wednesday after suffering a knee injury in the win over Geelong.

The 22-year-old landed awkwardly after a marking contest in the opening quarter of the match, with scans later revealing a low-grade medial strain.

Swans Head of Football Tom Harley says it means Sydney will make at least one change for the Grand Final against the Western Bulldogs.

“Aliir has done all he could to give himself a chance to play on Saturday. Unfortunately he was unable to complete training and therefore can’t be considered for selection this week.” Harley said.

“It’s always a tough situation for players facing some uncertainty over their fitness ahead of a game. Aliir is a young man of outstanding character and a bright future and he will be supporting the team on the weekend.”

Co-captain Jarrad McVeigh (calf) and Rising Star Callum Mills (hamstring) completed what was required of them at Wednesday’s session.

The teams for the 2016 AFL Grand Final will be named at 6.25pm on Thursday.