Collingwood captain Darcy Moore has failed to get up for Saturday night's date with modern day rival Adelaide, hobbled by a fresh injury concern.
Having battled through ongoing calf trouble, Moore left the track early with more soft-tissue problems.
Moore headed for scans and told Fox Sports that he had suffered a minor hamstring injury during training.
"Not a major one at all," he said.
"Like I said it's more awareness than anything. Clearly coming off a pretty big training block at the end of pre-season. Don't know what the damage is yet, but like I said, wasn't a disaster at all at all.
"Just enough awareness there to justify a scan."
Collingwood forward Jamie Elliott missed Thursday training through illness, but is expected to play against the Crows.
Magpies coach Craig McRae said his skipper tried his best to get ready for Round 1.
"Darcy won't get up," McRae said.
"Darcy had to get through a fitness test and unfortunately he has pulled up a bit sore. We don't know exactly what that means at the moment, but he won't play.
"I don't know (if it's the same calf issue). He left the track a little bit sore late, but I haven't had an update yet."
Collingwood conceded 63 inside 50s during its Opening Round win against St Kilda, with its defence under pressure throughout the match.
McRae said he doesn't know when the Magpies skipper will return to strengthen his side's backline.
"If it is something more sinister, we will report that later in the week," he said.
"We planned to play him. He has done all the work, he has had four, five, six weeks of pre-season now.
"There are a lot of threats (in Adelaide's forward line) isn't there? They have three big targets and we will have to plan accordingly. We survived last week without him and we will have to do something similar this week.
Fellow veteran defender Jeremy Howe is on track to return for Collingwood in Round 2 McRae hopes.
"We are planning to stick with the path at the moment with Howey," he said. "He has done about a month of training now and he looks like he is ready to take his spot whenever he is available."
