The condition of Melbourne superstar Christian Petracca is worse than first feared as the Demons bull remains in hospital following a heavy collision in Monday's loss to Collingwood.

Petracca was eventually subbed out of the King's Birthday clash due to a rib concern, with the Norm Smith Medal winner taken to hospital before the game had ended.

The 28-year-old copped a knee to the midriff in a marking contest during the opening term and remarkably returned to the game in the second quarter, only for the Demons to sub their star ball winner out of the contest at the main break.

Collingwood WON BY 38 POINTS

Petracca was spotted on the broadcast on a stretcher and being wheeled into an ambulance as he left the MCG in the care of medical staff.

The club has since confirmed Petracca has required surgery after suffering four fractured ribs, lacerations to the spleen and a small puncture in the lung.

Petracca then underwent a procedure to stop the bleeding on Monday night and remains in hospital.

The club has stated he is 'set for a stint on the sidelines', with a return to play timeline to be confirmed over the next week as the Demons seek further medical assessment.

"Obviously, Christian's health is the number one priority for us at the moment. The next few weeks will be crucial, and we'll be monitoring his progress closely to make sure he heals properly and fully. As his recovery progresses, we will look towards a return to play timeline,” Demons football boss Alan Richardson said in a club update.

“He's obviously an extremely important player for the team, but his health and recovery are our top priorities right now."

The Demons have a bye this week and will return in Round 15 against North Melbourne.