Collingwood star ruckman Brodie Grundy will be fit to face Brisbane at the Gabba on Sunday despite dealing with shin soreness.

Speculation was rife that Grundy would be sidelined after he had a scan earlier in the week following an injury flare up in last weekend's game against Richmond.

The big man has been carrying the complaint for several weeks, although Magpies football manager Geoff Walsh confirmed Grundy will play against the Lions.

"He's fine, he'll be OK. He'll play," Walsh told SEN.

Grundy is averaging 22.7 disposals and 35 hit-outs per game from six matches this season and would be the leading contender for All Australian ruck selection at this point.

Walsh also provided an update on midfielder James Aish, who will be sidelined longer, and potentially for up to three months, than initially announced on Tuesday.

Aish injured the posterior cruciate ligament in his knee against Richmond on Sunday.

"It's terrible for James because he had a great pre-season and is probably in career-best form. It's really heartbreaking for him," Walsh said.

"He will be braced (knee stabilised in a brace) for a month, we will see if that sticks in terms of the structure around the knee. If that works, then the brace will continue and there won't be surgery required.

"The month signpost will tell us whether this conservative treatment works. If the brace works and everything went to plan, it might be 10-12 weeks to get him back."

Walsh confirmed Darcy Moore (hamstring) and Taylor Adams (hamstring) were available for selection, while Levi Greenwood (knee) will play his first game for the season in the VFL.

Travis Varcoe and Ben Crocker will be available to play against the Lions after being rested for the game with the Tigers.