Melbourne defender Jake Lever is under a serious injury cloud and could potentially miss the remainder of the season after an incident during the first quarter of the Demons' big win over the Bulldogs at Etihad Stadium on Saturday afternoon.

Lever hurt his knee in the opening turn and hobbled off straight away, before going down into the rooms. He didn't return, with Demons doctors now fearing Lever has done his ACL, for the second time in his football career.

Lever sat out the 2014 season after knee surgery, which was his final junior season before being selected by Adelaide in the National Draft.

Fears were growing as the game progressed, with Triple M's Dr. Rowan White believe it could be a bad injury even if it's not the ACL.

"He was pointing to the outside of his knee," White said during Triple M's call.

"Could be a lateral ligament. Looks bad."

Melbourne defeated the Dogs by 49-points for their sixth win on the bounce.