MELBOURNE will be without midfielder Christian Salem for Sunday's clash against St Kilda at Etihad Stadium after he had surgery to fix a broken thumb.

Meanwhile, star Demons Jesse Hogan (ankle/knee) and Christian Petracca (finger) will have to pass fitness tests later in the week to be cleared to play.

Salem had an operation on Monday after scans showed a fracture at the base of his thumb.

The injury occurred in the second quarter of Sunday's match against Essendon, and Demons elite performance manager Dave Misson said the club hoped Salem would miss just one week.

"He had a guard put on it at half-time and re-strapped it – we didn’t want it injected, because we felt that it was going to affect his ability to handle the ball," Misson told the club's website.

"He had an operation yesterday afternoon to stabilise that fracture, so he's going to need to be reviewed post-op to see how the wound's going."

The Demons hope Salem will be available for the round eight clash against Gold Coast at the Gabba.

Misson said the Demons were hopeful Hogan, who copped a knock to an already sore knee and rolled his ankle in the third term against the Bombers, would be right to face the Saints.

"We'll assess him later in the week. At this stage he's looking OK, but he's got a little bit of work to do," Misson said.

"He's a professional player so we're hoping he'll be able to get up (against the Saints)."

Midfielder Petracca (infected finger) remains in doubt for Sunday's game against the Saints, but will be tested on Thursday.

"He's out of hospital, surgery went really well," Misson said.

"It's probably more about how we 'reload' him and get him ready for the game, but we'll just see how the wound looks."

In better news for the Demons, star midfielder Jack Viney is only a couple of weeks away from returning to play his first game this season.

"Jack is essentially out of rehab now. He's training with the main group so he did the flush and craft session with the AFL guys today (Tuesday)," Misson said.

"He'll train with the group on Thursday and it'll come down to how much work he needs before we tick him off to play; but it'll be a couple of weeks."

In bad news for Melbourne, young forward Harley Balic will be sidelined for up to two weeks with a foot problem.

Balic booted six goals in his first game at VFL level for Casey last month.

"Harley's just had a bit of plantar fascia (trouble) going on for a couple of weeks. He started running on the weekend and was pain free but it's probably a two-week turnaround," Misson said.