COLLINGWOOD'S Nathan Brown could find out on Monday if he requires potentially season-ending shoulder surgery, Magpies director of football Rodney Eade says.

The luckless defender re-dislocated his right shoulder on Saturday, in the opening quarter of his first AFL game since first injuring his shoulder in round two.

Brown flew sideways into a pack and his arm was caught awkwardly in the contest by West Coast ruckman Nic Naitanui.

The premiership backman immediately ran from the field and was later taken to hospital after Collingwood medical staff couldn't put his shoulder back in.

The 25-year-old had completed a solid rehabilitation and played three games in the VFL, but is now facing possible surgery.

"He won't play next week, he won't play for a few weeks and there's probably a real live possibility he may need an operation, but we'll know more when he sees a specialist tomorrow," Eade told AFL.com.au on Sunday.

"There's no real update. He went to hospital to get it put back in and it went OK so it's really just a matter of seeing a specialist.

"I'd imagine (the specialist) would probably have a fair idea which course of he's going to take (tomorrow), but I don't know."

There was better news for Jack Frost, who pulled up well after suffering concussion against the Eagles.

The young defender was forced from the field late in the second quarter and didn't return in the second half.

"He's pulled up pretty well today so we're hopeful that he'll be right next week," Eade said.

While Brown is set to miss an extended period, the Pies have a ready-made replacement in Lachlan Keefe, who performed strongly in defence in Collingwood's 40-point VFL win over Geelong on Saturday.

However, Ben Sinclair sustained a hamstring injury and could be facing a spell on the sidelines.

"Ben Sinclair hurt his hamstring, so we'll get a scan tomorrow on the extent of that," Eade said.

"We don't know until we get a scan; if it's a hamstring tendon it could be a few more weeks but we'll just have to wait and see.

"And Paul Seedsman just got a knock on the knee, just a collision sort of bone-on-bone, but he's OK, he's fine."