Despite a positive prognosis for Lachie Henderson after his third knee surgery in the space of seven months, Geelong is planning for his absence this season.

Coach Chris Scott said they had contingencies in place should Henderson's recovery stall after this week's surgery as the Cats' makeshift defence gets by without him and Harry Taylor (plantar fascia).

"We have no choice but to prepare for that," Scott said on Thursday ahead of a trip to face Port Adelaide.

"Fortunately the news on Harry Taylor is more positive. We expect to get him back a lot quicker than Lachie.

"The experience we've had over the first four rounds will help when we actually do get one or both of them back. We've got contingencies.

"In a perverse way, it's actually good for them (young defence) to be under the pump and find a way to prevail."

Scott all but ruled out emerging key defender Timm House for a debut against the Power but admitted he was on their radar following strong VFL performances.

Just four days after the club feared that Cory Gregson may have re-injured his troublesome navicular bone, the small forward moved freely at training away from the main group.

However, he remains likely to miss at least this week, and Scott said last week's carryover emergency James Parsons headlined a list of potential replacements.

"It's not out of the realms of possibility that he (Gregson) could be up and going in a couple of days, which might keep him in the frame for this week. But the more likely scenario is that he might miss a game or two," Scott said.

"James Parsons missed last week, he's been an important player for us, it would be likely that he would come in.

"We're getting more and more confident that Charlie Constable is an AFL player – we probably thought that through the pre-season, so he's pressing his case."

"We're liking George Horlin-Smith's (VFL) form; if we chose to go a little bit taller, Zac Smith played well for us last week in the ruck.

"That's a constant conversation amongst our coaches and our match committee group as to how we manage those guys and whether we can play them (rucks) all together. All options are on the table."

Scott said he was pleased to hear Smith tell local media this week it looked unlikely both he and Rhys Stanley could feature in the same 22.

"I think that's a good attitude for him to take, (but) we're open to the idea of them both playing," Scott said.

"There are other factors that influence that – Ratugolea coming into that mix playing a little bit in the ruck and we've got Blicavs as well."

Stanley joined Ratugolea with Mitch Duncan and captain Joel Selwood in centre clearance work, a hint that they may play the same duo in consecutive weeks against a depleted Power ruck set-up.

Superstar Patrick Dangerfield ran laps after a "corked calf" last week, with Scott saying there was no doubt in him lining up on Saturday night.

Injured defender Cam Guthrie was spotted on a recovery scooter after surgery on his syndesmosis, and Nakia Cockatoo had his left knee in a brace after his PCL injury.

The Cats return to Adelaide Oval for the first time since their preliminary final loss to Adelaide missing at least eight players out through injury, trade or retirement – including ex-Cat turned Power midfielder Steven Motlop.