Collingwood ruckman Mason Cox will miss the AFL blockbuster against Richmond at the MCG after complications with a rib injury.
Cox damaged the area during the Magpies' round-two win over Port Adelaide, with the club initially believing it was just bruising.
However further investigation revealed a haematoma, which could sideline the 32-year-old for a number of weeks depending on the result of further scans.
"I've had better days, so (I'm) out for the Friday match against Richmond," Cox told KIIS 101.1's Jase & Lauren on Thursday.
"It is essentially a bit of bruising inside the rib area and a bit of internal bleeding.
"I went in (to hospital) yesterday and got scans and bloods drawn. It has been a big 24 hours."
While he will definitely miss Friday's clash with the Tigers, Cox hopes to be back in action in time for the Anzac Day clash with Essendon.
"My parents are coming to town (for the Essendon match), so I'm hoping I can make that one," he said.
"That's the one I definitely want to be there for but it is up to the doctors."
Collingwood's General Manager of Football Graham Wright said in a statement: "Mason's health is our priority here - he will now undertake further scans before we determine a timeline for his return."
