ST KILDA'S almost non-existent injury list has ballooned after a horror weekend, with Paddy McCartin and Sean Dempster unavailable until after the bye and skipper Nick Riewoldt no certainty to face Carlton at Etihad Stadium on Sunday afternoon.

It comes on top of news that young defender Hugh Goddard will have surgery on a ruptured Achilles tendon in his left leg after being taken from the ground on a stretchee in the 88-point loss to Adelaide last Sunday.

The stretcher was again put to use again for McCartin after he was concussed in the third term when hit in the head by teammate Jack Newnes and then Adelaide's Luke Brown immediately afterwards.

"Paddy won't play this week. It was precautionary to send him to hospital during the game at the weekend," Cox said at the club on Tuesday.

"He's OK, he's recovering fine."

Initial concerns about McCartin's neck were allayed, and Cox hoped the forward would miss just one game, with the Saints having a bye in round 13.

"You don’t mess around with these things. He'll certainly be tested coming out of the bye. We'd like to think at the moment he'd be fit for the game after (the bye)."

McCartin was concussed against Collingwood in round three earlier this year, and also suffered the injury in the VFL last year.

It was also an issue when playing in the under-18 championships, when a bump on West Australian skipper Dom Sheed (now at West Coast) caused the No. 1 NAB AFL Draft selection in 2014 to have delayed concussion.

Dempster had surgery on Tuesday on his right knee after pulling up sore in the third quarter against Adelaide.

He played out the game but will miss four weeks.

"He had a bit of cartilage floating around his knee," Cox said.

He also said Riewoldt was only a 50-50 chance to play this week after copping a knock against the Crows.

"We won't know really how Nick's travelling until later in the week," he said.

"The procedure was positive, and it gives him a chance (to face the Blues)."

Cox said Riewoldt had not been experiencing any issues with his previously troublesome left knee.

"Until that knock, (his knees were) good as gold. He'd had no awareness whatsoever," he said.

Cox confirmed St Kilda's worst fears with Hugh Goddard's season over after surgery on his ruptured Achilles.

Goddard was injured after an innocuous incident in the second quarter against Adelaide as he pushed off his left leg.

"He's already got a text message via Nick Riewoldt from Jarryd Roughead, who had a similar injury, tohelp out and hopefully encourage him," Cox said.

Injury-prone midfielder Nathan Freeman also hurt his hamstring at training last Friday night.

"In isolation … it's about a 3-4 week hamstring. Given his frustration I suppose, and given it's another incident, we'll reassess Nathan's progress from here," Cox said of Freeman.

The Saints have already looked at different ways to build up Freeman's body, and Cox said the club would continue to explore its options with the 20-year-old.

"We've completely changed his program, and there are a lot of really positive signs," Cox said, acknowledging that Freeman might not be seen on the field again in 2016.

"Part of our motivation is to get him up playing some form of footy, because he hasn't for a while, but there is a possibility (he sits out the season)," Cox said.