SYDNEY coach Dean Cox expects unfavourable news about Callum Mills' knee injury after the captain was forced off in the first quarter of the Swans' 53-point qualifying final victory over Brisbane.

Mills left the field early after his right knee collapsed while changing direction on the boundary line. Clearly in pain and unable to bear weight, he required assistance from trainers and was promptly ruled out for the remainder of the game.

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Speaking post-match, Cox expressed deep sympathy for the skipper and promised the club would give him full support throughout his recovery.

"So, obviously not expecting great news on Callum, and in the next couple of days we'll find out the extent of that, which is devastating for him and the footy club," he said. 

"We'll do whatever we can to support him through whatever it is that he will go through."

When asked if Mills had suffered a torn ACL, Cox confirmed the seriousness of the injury and admitted the initial outlook was grim.

"It's a knee, yeah," he said. 

“We're not sure exactly the full extent of it, but yeah, it doesn't look good. We'll work out exactly what it is in the next day or two."

Left on crutches, Mills rallied his team from the bench and praised its spirit following a turbulent stretch for the club.

"We'll figure it out later," Mills told Channel Seven post-match regarding his knee.

"It is what it is. I'm just so proud to be a part of this group. That was a special win. Sitting on the bench and being a part of it was incredible. I hope everyone here who felt it today feels the same because I'm really proud to be a Swan."

Despite losing Mills early, the Swans reset and dominated the contest. Cox praised his squad's maturity in overcoming the initial shock of seeing their teammate injured, noting how they refocused and relied on their system and defensive effort to stay in control.

"The maturity of the group to be able to see what happened – it didn't look great from the outset – and then to rally and stay on task and focused on what they had to do was a credit to them," he said. 

"They've spent a lot of time working on moments where they need to refer back to what they can control, and they control that by pressure, system, and role, and they did that."

The loss of Mills triggered an immediate reshuffle, with Jake Lloyd floating back to fill the void. Losing their skipper further compounds an already difficult task for the Swans, who entered the final severely depleted following five club-imposed suspensions.

There was also a pre-game injury scare for Tom Papley after the star forward appeared uncomfortable while speaking with trainers and heading to the rooms during warm-ups.

However, Cox confirmed Papley was fully fit and praised the energetic forward for bringing valuable leadership, confidence, and execution to the team as he kicked five goals.

"'Paps' (Papley) has been OK," he said.

"He trained the whole couple of sessions this week. Going into the game, he knew exactly the role that he had to play, and he's done it really well. I think the energy he gives, but also the confidence he gives some of the young forwards that are playing around him – they look to him, and he delivered really well.”

Now, with a week's break before hosting Fremantle or Geelong in a preliminary final, the door opens for some injured stars to return.

Key forward Joel Amartey and midfielder Justin McInerney are in a race against time to be fit. Amartey has successfully resumed full team training and completed key benchmarks in his recovery from an Achilles injury, while McInerney has also returned to full team training as he ramps up his workload following a hamstring issue.

Cox expressed confidence that the pair will be fit to play.

"Yeah, they will be. They should both be available," he said.

"That's what you want, a team where players that haven't been playing through injury have got another couple of weeks now where they can train extremely hard over that period and put their hand up for selection."

When asked how the selection panel will weigh up bringing Amartey back into a forward line where all the tall forwards performed strongly, Cox insisted their strategy remains unchanged.

"That'll just be a decision like we do every week," he said. 

"We'll pick the best team to beat the team that we play against. That won't change."

Playing with their backs against the wall after a difficult few weeks, Cox expressed pride in the team's performance against a strong, in-form opponent, noting how the victory showcased their unity, resilience, and hunger.

"Extremely proud of everyone at the footy club to deliver a performance like that against a team that was in the form that they were in," he said.

"It was a real sign of a galvanised group who were hungry to show that they're capable.

"I still had the belief in the playing group that we were capable of putting in a performance like that leading into the North (Melbourne) game. To have a couple of days to really regroup, spend time looking at Brisbane, and spend a lot of time training; I was really proud. When young kids come into our team and execute their roles at the right time, making the right decisions in the moment, they do extremely well."