He will have a scan on Monday and anything more serious than tightness could sideline him for the remainder of the Swans' flag tilt, with a preliminary final in just under two weeks and the Grand Final a week later.
"I'm not sure how bad (it is), but he seems pretty positive, so fingers crossed that it all goes well for him," said Rhyce Shaw, the Swans’ other dynamic rebounding half-back.
"It doesn't seem too bad, but we won't know anything until that scan tomorrow morning.
"Hopefully he gets back because he's a really important player for us and I certainly want him out there. He's fantastic."
One option for coach John Longmire if Malceski doesn't make it back for the preliminary final is swinging co-captain Jarrad McVeigh into the vacant position, which he dropped back to fill on Saturday.
Shaw, who has suffered his share of injury woes over the past two seasons, tried to lift the spirits of his good mate Malceski after he came off the ground.
"I just said 'keep positive, we'll try and do the best we can and try and get the win so he can get an extra week to recover and hopefully get back for the prelim'," Shaw said on Sunday.
"We're pretty close, so I just got over to him and gave him a bit (of support)."
Shaw, who like Malceski has undergone LARS surgery on a knee, found some form against Fremantle in his third game back from an ankle injury, racking up 23 disposals against the Dockers.
"It was really important to get those two games in before the final, I wasn't playing great footy in those games," Shaw said.
"But I got some form last night and that was the main thing."
Shaw said having a week off was definitely an advantage after such a tough and taxing game.
Meanwhile, Shaw implored dasher Gary Rohan to keep running and chancing his arm despite his error-marred first half in Saturday's qualifying final win over Fremantle.
Speedy Rohan made errors which led to Fremantle's first two goals, and had two wildly inaccurate shots for goal in the second quarter.
Rohan was much more productive in the second half, as he continued to back himself after getting the support of his teammates.
"We just told ‘Gaz’ to run as fast as he can and hope for the best," Shaw joked.
"We want Gaz to break the lines and that's what he's in the team for.
"Those skill mistakes, they will come. I used to make a thousand of those when I was younger, so it doesn't really matter.
"You get over that and you mature as you go along.
"But at the moment we want Gaz to defend and to break the lines and he was doing that.
AFL Captain Callum Mills reads messages sent to him after his ACL injury late this season.
14:30
A gruelling wet weather win against the Lions | Inside Sydney
See behind the scenes for an extensive look into the first in club history win against the Brisbane Lions at Henson Park. With a heartfelt send off for Kate Mahony and a shared team song with loved ones, this one was one to remember.
07:54
AFLW full post-match, RD7: Swans
Watch Sydney's press conference after round seven’s match against Brisbane
05:16
AFLW Highlights: Sydney v Brisbane
The Swans and Lions clash in round seven of the 2026 NAB AFLW Season
See the latest update on Sydney's AFLW squad, presented by Castlereigh Imaging.
Alex Neyland re-signs until 2029
Sydney Swans utility Alex Neyland has re-signed with the club, putting pen to paper on a new deal until at least the end of 2029.
2026 Sydney Swans AFL Awards - all you need to know
Ahead of the evening, take a look at the history behind the awards and how votes are awarded.
Academy talents named in inaugural Indigenous and Multicultural Futures program
QBE Sydney Swans Academy products Pharrell Trapman and Oliver Sheridan have been named in the inaugural AFL Indigenous and Multicultural Futures Squads to head to Melbourne for a football camp and showcase match this week.