STEVEN May has been ruled out of this weekend’s clash with St Kilda, as he faces a minor hamstring setback.

The key defender is among three changes for Melbourne’s Round 19 game, with Braydon Preuss and Jay Lockhart both omitted from the side, allowing Oscar McDonald, Oskar Baker and Tim Smith to return.

May’s injury appears to be on the minor side, but General Manager of Football Operations Josh Mahoney said the club was being cautious to ensure no further damage is done.

“Steven had an incident in the third quarter last weekend but played out the game without any restrictions,” Mahoney said.

“He pulled up well this week, but he had some scans which showed a low-grade strain.

“We’re confident this won’t keep him out for too long, but we won’t be taking any risks.”

May’s exclusion provides an opportunity for McDonald to play his first senior game since Round 11, after the defender took some time off mid-season to get his body right.

Smith, who has also had challenges with his body, had a run in the VFL last Saturday after straining his calf against Brisbane four weeks ago.

The Dees’ emergency list this week consists of Preuss and Kyle Dunkley, as well as Sam Weideman and Marty Hore, who will both look to get some match fitness under their belts in the reserves as they return from respective injuries.

The Casey Demons will travel to Sandringham on Sunday, allowing all four of those players to take the field, provided they’re not required on Saturday night.

Check out the full side to take to Marvel Stadium below.