Premiership ruckman Darren Jolly is no certainty to play this week after pulling up sore from his comeback game in the VFL on Sunday.

Jolly has not played since round 12 and has managed just nine games this season. He returned to the VFL but looked hampered by his knee injury.

Collingwood coach Nathan Buckley said Jolly was "touch and go" as to whether he would continue this week and his availability will be an ongoing issue to manage for the rest of the season.

Buckley praised the efforts of 19-year-old ruckman Brodie Grundy, who he said was jumping better than any ruckman in the team.

Grundy has played just two games but has already stamped himself as an exciting prospect.

"He's showing us some attributes that are going to be really positive for us in the long term and possibly in the short term," Buckley said on Wednesday.

He said Ben Hudson and Jarrod Witts were making competition for the ruck spot tough.

"Clearly someone is going to own that role at some stage in the next month and we have got time to find out," Buckley said.

Buckley said Dale Thomas had surprised the coaching staff with the way he moved on the track in his first serious hit out but he would not return to the VFL for another week
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"He moved around pretty well," Buckley said. "We're encouraged by where he is at but he still has got a few more boxes to tick and as I said all along it's probably a bit of a stretch to expect that 'Daisy' is going to be able to come back and give us a great deal.

"But from what I have seen it's becoming more of a possibility.

"I am happy for him to keep on proving us wrong."

Hawthorn recruit Clinton Young, who has most recently battled a hamstring problem during an injury-interrupted season, was still in contention if he could squeeze a finals game in before season's end.

Young has played just two senior games since joining Collingwood but Buckley said he had shown enough to indicate he could make a valuable contribution if fit.

However the coach said the Pies had been forced last year into taking players into the finals that were less than 100 percent fit and would not be doing so this season.

He said Dane Swan's absence from training was due to the midfielder needing to freshen up with a six-day break between games. Swan knocked his knee on Sunday but Buckley said he would play against the Swans.

"We're looking at trying to manipulate and manage our playing list so we're cracking at the right time of the year and we feel like we have still got a lot of improvement in us," Buckley said.

He said the club was firmly focused on beating the Swans this weekend.

"They (Sydney Swans) have not had things all their way this year, taught us a lesson in round nine, hard two way running, really clean with the ball when they had it and pressured us when we had it," he said.