Geelong star Patrick Dangerfield has been overruled by the club's medical staff after putting his hand up to play a week after suffering a cracked rib and a partially collapsed lung.
The captain's first game in six weeks was ruined last Thursday night when he was hurt during a marking contest in the second quarter of the loss against Port Adelaide.
Dangerfield bravely played out the match at Adelaide Oval but was forced to drive the eight hours home to Moggs Creek, rather than flying with the rest of the team, due to the severity of his injuries.
Cats coach Chris Scott was optimistic the 33-year-old would be available for next week's round-16 match against Sydney but said the player would miss the clash with Melbourne at GMHBA Stadium on Thursday night.
"I fully expected him to declare himself fit, which he did, and he was just overruled on that one," Scott said.
"Not by as wide a margin as I expected.
"He thinks he could play. As is often the case with those guys, you've got to save them from themselves.
"(The medicos) say if the game was Sunday, Monday then he'd probably be OK to play, so that's a good sign for the following week."
Geelong assistant coach Nigel Lappin famously played in the 2003 grand final for the Brisbane Lions with a broken rib, complicated by suffering a punctured lung during a pre-game fitness test.
But Scott said clubs did a better job of protecting injured players than they did during his own playing days.
"I don't mind saying publicly, I just have absolutely no desire to put any of our players out on the ground who are inhibited," he said.
"That is a product of the past. It happened way too much in bygone eras - and we're not going to let it happen at our club.
"So Paddy could have declared himself fit and demanded that he was going to play but if this were a grand final, we still wouldn't let him play."
The blockbuster clash with the Demons - Scott's 300th as Geelong coach - is a vital one for the 10th-placed Cats as they attempt to stay in touch with the top eight.
Last week's defeat to the Power left Geelong 6-7 in their premiership defence.
While Geelong lose Dangerfield, they will welcome back premiership ruckman Rhys Stanley for his first game since he suffered a fractured right eye socket in April.
"It's exciting for us," Scott said.
"We literally did not have a ruckman on our list (against Port) besides (Mark) Blicavs, so getting Rhys back is going to be a real bonus for how we choose to play."
After being comfortably beaten in the corresponding match last year, Melbourne will take the unusual step of spending the night in Geelong on Wednesday and training at GMHBA Stadium, a notoriously difficult ground for travelling clubs.
Star midfielder Clayton Oliver is no certainty to return for the Demons after missing the King's Birthday win against Collingwood due to an infected blister that hospitalised him for almost a week.
