COLLINGWOOD midfielder James Aish will be sidelined for more than a month with a PCL injury to his knee, while Ben Reid and Brayden Maynard are also out of Sunday's match against Brisbane at the Gabba.

Aish injured his left knee in Sunday's 43-point loss to Richmond, with Magpies football manager Geoff Walsh providing an update on the treatment methods the Magpies will use.

There is a chance Aish may require surgery once he is reassessed at the one-month stage of his rehab.



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"It's a long-term injury. He'll be braced (his knee stabilised in a brace) for four weeks and then we'll have our doctors reassess that at the end of the four-week period, and if that's the case, we'll continue with that conservative approach of his rehab," Walsh told the club's website.

"If, at the four-week stage, it (Aish's knee) hasn't improved to the extent that we'd hoped for then there may be some sort of surgical intervention."

Reid suffered an Achilles injury late in Sunday's game against the Tigers and is looking at a fortnight out of the game.

"Pleasingly that's not too serious. Certainly I would think Ben is a 1-2 week proposition, but fortunately he got out of it without anything more serious than that," Walsh said.

Maynard is unlikely to get up for Sunday's clash with the Lions but will be reassessed later in the week.

"I would think Brayden is a one to two-week proposition on the sidelines. He may improve over the next three to four days and that might be something we would vary, but I think it's safe to say he'll miss this week and we'll see how he is in seven to 10 days," Walsh said.

WATCH: Aish hurts his knee against Tigers

In better news for the Magpies, Taylor Adams (hamstring), Darcy Moore (hamstring), Josh Smith (hamstring) and Levi Greenwood, who is yet to play at any level this season because of a knee injury, are all ready to return.

Walsh said a decision on selection, whether that be AFL or VFL, of the quartet would be made later in the week.

Travis Varcoe and Ben Crocker, who were both managed for the match against the Tigers, are available to play, while Tom Langdon will be tested later in the week.

Meanwhile forward Jamie Elliott will join in main training for the first time this week as he comes back from a hamstring injury. Walsh said the spring-heeled forward would need at least a fortnight in main training before being available for selection.

Collingwood will provide an update on the health of Kayle Kirby later in the week once the test results on his heart are returned and examined by the club's medical staff.

Kirby collapsed in a VFL game at the Holden Centre in late March due to an irregularity in his heart beat.