Collingwood remains in the dark in regards to midfielder Jordan De Goey's latest setback, with the Magpies unclear on the extent and timeframe for a return for the premiership star.
De Goey was withdrawn from the club's Round 20 side to face Richmond due to a groin injury, with the Magpies having the 28-year-old undergo fitness testing over the weekend before putting a line through his playing prospects.
The gun onballer missed multiple weeks earlier in the season due to a groin injury and faced an extended period on the sidelines after dealing with a subsequent abdominal setback.
De Goey returned in Round 16 after five weeks out of action but is back in the club's casualty ward with a groin issue that has limited the 17-gamer.
Coach. Craig McRae flagged after Sunday's win that the club was unsure whether De Goey would be fit in time for this weekend's blockbuster clash with Carlton, with the premiership coach still having doubts over De Goey's chances.
Speaking on Tuesday, McRae said the club's medical team was continuing to assess the extent of De Goey's current ailment, which has him in a "grey category".
"I'm unsure, I really am," McRae revealed.
"I think our medical team is unsure, which probably puts him in the grey category."
When asked if De Goey may potentially require surgery in the off-season, McRae said it was doubtful but remained uncertain.
The Magpies are likely to be bolstered for Saturday's clash - which will celebrate ex-captain Scott Pendlebury's 400th game for the club - with as many as three players expected to be available to return.
Forward Beau McCreery is likely to come into McRae's side after missing the past month with a calf injury, while Oleg Markov (personal) and Nathan Kreuger (concussion) were absent for the win over Richmond and are in line for comebacks of their own.
"We're a bit more certain about those three," McRae said.
"They trained over the weekend and trained well. Here we are on Tuesday, so there's a bit of time.
"All going to plan those three would be available for selection."
The MCG is likely to see more than 90,000 fans flood into the venue as arch-rivals Carlton and Collingwood battle to keep their seasons alive with a month to go.
If the occasion wasn't big enough already, Pendlebury's milestone has provided a further buzz around Olympic Park, with every Magpies player keen to play a role this weekend.
"I don't really want to talk up games, but this is a big game. This is the one that we write down in our calendar and we want to turn up for this one," McRae added.
"We've got one of our greatest ever players celebrating a huge milestone against our biggest rival.
"There's a buzz, because there's an excitement of what is coming and everyone wants to play in this game for Pendles.
"All those guys that are maybe a little bit sore might use a little less ice this week. Everyone is up for this game."
Collingwood will host Carlton at the MCG on Saturday at 7:30 pm (AEST), with a win for the Magpies potentially taking them back into the top eight.
