COLLINGWOOD will use a smaller backline to tackle Sydney and Lance Franklin on Saturday, with coach Nathan Buckley resisting the urge to recall father-son key defender Will Kelly.

The Pies will be forced into two changes with full-back Jordan Roughead joining Nathan Murphy on the sidelines due to concussion.

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Kelly loomed as a like-for-like fit, however Buckley conceded the 20-year-old's return for a solitary game Anzac Day was only a short-term fix and that he needed to see more from the youngster in the VFL.

"We'll definitely miss Roughy, he's been a really strong key defender for us over the time so we may be a little smaller than we have been in previous weeks," Buckley said.

"It's not something we're too concerned about, we believe we'll have aerial support or aerial cover to get the ball to ground and then that'll be one part of how we plan to defend Sydney.

"He's (Kelly) working a way through the VFL system as a key back at the moment and we're looking for him to put a block of form together before we bring him back in."

Darcy Moore is expected to spend time opposed to Franklin, with Mark Keane to fill the other key post. Jack Madgen, who was dropped after Anzac Day is in the frame for a spot, along with ex-basketballer and uncapped Category B rookie Tom Wilson who is "definitely putting himself around the mark" as an intercepting defender at VFL level.

Buckley said both Murphy and Roughead had passed concussion tests following last week's win over North Melbourne. However, while Murphy actually failed his, Buckley said the Pies would err on the side of caution with Roughead due to his history of head knocks.

"'Murph' was the one that told me he'd passed the concussion test, maybe I shouldn't be listening to the player because he didn't pass the test," Buckley said.

"'Roughy' passed the one on the night and has passed subsequent tests but as we know the club doctor takes the lead in that and it's a medical process."

Finlay Macrae, Jay Rantall and last week's medical sub Callum Brown are in line for a spot in the starting side, however Brayden Sier looks unlikely to win a reprieve after limping off the training track on Thursday and being sent for scans.

And Buckley joked that he wouldn't be seeing spearhead Jordan De Goey in the midfield should last week's form continue. "If he's going to kick six every week, I reckon we'll leave him there," Buckley said.

The Pies will travel along with their VFL squad on Saturday to the SCG, with the Pies' reserves to face the Swans' reserves following the AFL game.