GEELONG midfielder Mitch Duncan will be out for up to three months after scans revealed he has a broken foot.

The Cats' star will undergo surgery, with Geelong indicating Duncan will sidelined for 10-12 weeks.

Cats doctor Drew Slimmon said Duncan had fractured the fifth metatarsal, a bone on the outside of the foot, during the club's loss to the Sydney Swans on Saturday night.  

"That injury often requires surgery, and that's what we're looking at doing for Mitch to give him the best opportunity of getting back as quickly as possible," Slimmon told the club's website.

After a slow start to the season playing in a series of different roles Duncan was back to his best form in recent weeks playing in the midfield.

He racked up 29 disposals and two goals against Richmond in round five, before amassing a career-high 38 possessions against Collingwood in round six. He had 18 disposals against the Swans before being substituted out in the third quarter.

The positive 24-year-old described the broken foot as "a bit annoying" but he hopes to play again before the end of the season.

"I was just running, went to change direction and felt a little pop in my foot," Duncan told geelongcats.com.au

"I thought one of my studs had actually come off, but that wasn't the case.

"Hopefully … I'll be able to come back and contribute to the team in any way I can."