MELBOURNE remains hopeful Christian Petracca will be fit for Friday night's blockbuster semi-final against Brisbane, though there is doubt over small forward Charlie Spargo after a nasty throat injury.

Petracca trained both on Monday and Tuesday after suffering a hairline fracture to his fibula and a significant contusion to his calf having been kicked in the back of the leg by Swans superstar Lance Franklin last weekend.

The reigning Norm Smith Medal winner played out the qualifying final loss to Sydney, but was heavily impeded by the injury and struggled to have his typical trademark influence on the contest.

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Although he is still suffering some pain as a result of the incident, the club's doctor Laura Lallenec said she is confident the fracture is stable enough to ensure he will be able to play against the Lions on Friday night.

"He was kicked in the back of the knee during the game," Lallenec said.

"What actually happened was his tib-fib joint, which is where his fibula meets his knee, had an instability event. Essentially, it was a sprain of that joint and a little fleck of bone ended up chipping off that hairline fracture at that tib-fib joint level.

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"Really, we can treat this like a sprain. The harder bit of the injury was that he had a big kick to his calf, which resulted in a corkie essentially. That was actually bothering him more. We were a little bit more worried about that, with the swelling.

"Thankfully, he's really settled down. He's done everything right. We've discussed his injury with a specialist and they're really happy that this injury is stable and that he's safe to get out there and play.

"Today was about getting him out to training, making sure that he's functional and able to run around and that he's comfortable. He's really proven that today, so at this stage he's looking really good to get up for the captain's run on Thursday and play on Friday."

Spargo copped a stray elbow to the throat from Sydney defender Tom McCartin, also playing through the game under some duress. Scans have since cleared him of any fracture to his airway, though there is significant swelling.

The dangerous small forward has seen specialists in the days since, but will still have to undergo a series of fitness tests later this week to determine his availability for Friday night's do-or-die contest.

"He had a heavy knock in the game," Lallenec said.

"Thankfully, scans have cleared him of any fractures in his airway. But he does have some bruising around his vocal cords. That's something we worry about and we like to keep a really close eye on.

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"He's been seeing a specialist every two days. He had a camera down his throat to make sure that swelling is improving, which it definitely is. It's been really precautionary, looking after him early this week so that we can get him going later in the week aim to have him available for Friday."

Melbourne forward Bayley Fritsch will be fit to feature, despite suffering a knock to his knee during the warm-ups last Friday night, while midfielder James Jordon is still a fortnight away from returning after a foot problem.