MELBOURNE defender Oscar McDonald has been cleared of serious damage to his left ankle and the Demons remain hopeful he will be fit to take on St Kilda at Etihad Stadium on Sunday.

In further good news, star Demon Bernie Vince is almost certain to face the Saints despite struggling through last Saturday night's game against Fremantle in Darwin with a painful shin injury.

McDonald injured his ankle in the third quarter of Saturday night's clash against the Dockers and was placed on crutches immediately after the game.

However, Melbourne football manager Josh Mahoney said scans revealed a positive outcome.

"Oscar sprained his ankle during the third quarter of our game in Darwin," Mahoney told AFL.com.au.

"He has been cleared of any major damage and is improving every day. He is a chance to play this week."

McDonald also rolled his left ankle against Greater Western Sydney in round one and missed the following week's match against Essendon.

If McDonald is ruled out, the Demons could turn to either Lynden Dunn or Colin Garland to support incumbent defender Tom McDonald in the backline.

Dunn, who has not played at senior level since round six, played his first game in almost a month at VFL level against Richmond on July 3 after making his return from a hamstring injury.

The Casey Scorpions had a bye at the weekend, which would have allowed Melbourne to give Dunn the appropriate conditioning he missed out on during his time on the sidelines through injury.

However, with Dunn playing limited game time over the past month his lack of footy may be a factor the Demons consider in whether he is picked.

Garland has played six games this season and last appeared at AFL level in round 10. The versatile defender has played well in patches at VFL level, but the Demons have been asking for more consistency before elevating him.

Young defender Josh Wagner will also come into the selection mix after missing the Demons' past two matches with a knee injury.

Wagner, the Demons' first pick in last year's Rookie Draft, did not miss a game before the injury, after being elevated to the senior list and making his debut in round three.

Veteran defender Heritier Lumumba has been ruled out of VFL action again this weekend as he continues his recovery from another concussion.

The Demons carefully managed Lumumba after his first head knock and gave him a long lay-off after concussion symptoms lingered.