Collingwood defender Jeremy Howe is hopeful he will be fit to take on Sydney in Saturday night's clash at the SCG.

The Magpies star was ruled out of Saturday afternoon's game against Richmond in the first quarter after he suffered concussion when he was collected by Darcy Moore's errant knee in a marking contest.

After a spell of "dizziness" in the immediate aftermath of the incident, the defender said he was feeling much better and will look to prove his fitness at training on Thursday.

"It's only Monday so the signs are positive and I feel good. Training's not until Thursday so I don't really have to do anything physical until then," Howe told reporters on Monday.

"I'll save myself, recover well, tick the boxes and see how I go."

Howe said he was feeling clear in the head and is confident he will be able to train fully at main training on Thursday.

"It wasn't ideal to get a head knock early in the game, but in terms of the way I've pulled up I haven't had a headache or anything," Howe said.

"I've got a nice little lump on the top of my head, thanks to 'Darce'.

"But no scans on the head. I've pretty much done all the precautionary things as expected so I've just got to see how the week plays out."

With Howe no certainty to get up and Matthew Scharenberg almost certain to be ruled out for the rest of the 2018 season, with fears he may have ruptured the anterior cruciate ligament in his knee for a third time, Collingwood's defensive stocks have been decimated.

Lynden Dunn, who tore his ACL in round 15, is out for the year, while Tyson Goldsack, who ruptured his ACL in the JLT Series, is at least still a few weeks away from making a faster than expected return to the field.

Howe said the injuries would give youngsters such as Nathan Murphy or Jack Madgen – who was elevated off the rookie list last week – an opportunity to come into the side.

Murphy was taken with pick No.39 in last year's NAB AFL Draft and has been developing nicely in multiple positions at VFL level, while Madgen is a former basketballer who was taken as a mature-age category B rookie.

"Our back stocks are getting pretty low. There's no shying away from that," Howe said.

"Young Nathan Murphy's been thrown around as a bit of a swingman at half-back and half-forward.

"Jack Madgen's been elevated from the rookie list so he's been performing really consistently. He's a bit more of a lockdown defender and he tips into his game more than most and he's been performing at VFL level.

"So someone's going to get their opportunity at some stage and I'm looking forward to what they bring when it comes to game day."