Carlton are holding their breath after superstar captain Patrick Cripps limped off the training track with a knee injury.
Cripps was slow to get up after landing awkwardly during match simulation.
He briefly tried to continue before taking himself from the ground where he was attended to by medical staff.
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The 28-year-old already had heavy strapping on right knee and completed a series of run-throughs on the boundary line before removing the strapping.
He then watched the remainder of the session from the sidelines.
Patrick Cripps injured his knee at training. Credit: Twitter @aflratingsPete
The gun midfielder was later pictured smiling with fans in a positive sign.
A serious knee injury would be a hammer blow to the Blues ahead of the 2024 season where they are expected to be among the premiership challengers.
Carlton enjoyed a fairytale return to the finals this year, beating Sydney and Melbourne before falling to Brisbane in the preliminary final.
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Cripps this week was hosed down the growing expectations at the club.
“I actually hate the word ‘expectation’ because you’re trying to pick something that hasn’t happened yet,” he said.
“We learnt a really hard lesson last year and I felt like the group lost their confidence through that middle part.
“Through that adversity we learnt that we know what we can focus on to make us a good side.
“The external (hype) doesn’t really matter. What matters is what we value internally.”
Carlton’s narrow finals wins over the Swans and Demons marked their first September successes in a decade.
On the back of that, Cripps said there had been a noticeable shift in the playing group’s mindset at the start of pre-season training when compared to a year ago.
“The whole energy around the club is definitely going forward together,” he said.
“When you do get a taste of it (finals), it really drives you to keep going
“Our group’s stayed together for a period of time now and we’re still trying to find ways where we can keep levelling up a bit.
“To get so close last year just drives that motivation but we still feel like we’ve got a lot of natural development left.”