TO MAKE up for the loss of James Rowbottom's relentless tackle pressure, Sydney coach Dean Cox says the Swans must rethink their midfield dynamics and master player rotations to sustain their top-tier intensity.

While Sydney notched a 19-point comeback win over St Kilda on Saturday, the victory was overshadowed when the key midfielder broke his hand — an injury requiring surgery that has ruled him out for the rest of the home-and-away season.

Losing Rowbottom so early in the match deprived the Swans of their primary defensive midfielder, who currently ranks fifth in the League with 124 tackles. The team's sluggish defensive start — recording just seven tackles in the first quarter and barely any midway through the second — further underscored his absence.

"For the first quarter, we had about seven tackles, and halfway through the second we hadn't had many at all," Cox said on Thursday.

"So we injected Braeden (Campbell) in around the ball, and he was the one that had about three in a couple of minutes.

"So, we need to look at the dynamic of that and what that looks like — … the players that we do put through the middle of the ground. What we want is to complement each other through every area of the ground, and the midfield is one; without James we need to look at it intensely."

Inside midfielder Angus Sheldrick is the leading candidate to replace Rowbottom after posting 25 disposals and a goal in Sydney's VFL loss.

However, Cox noted that the coaching staff must weigh how his inclusion impacts the overall dynamic and balance of both the midfield and the forward line, rather than making a straight swap.

"He's in the mix," Cox said of Sheldrick.

"I think one thing as well that you want to consider in the mix is how does our midfield look, and also ahead of the ball? So that's something that we're deliberating on at the minute now. Is it just a straight swap, or is it something different that we saw throughout probably the last half against St Kilda as well?"

Despite the setback, the Swans remain confident their defensive cornerstone will return for finals.

"Oh, definitely, I'd expect him (to)," Cox said.

"Time-frame wise, unsure; it could be before the finals. So, we'll just work through what exactly that looks like, how he responds to it, how it's feeling, the dialogue from the surgeon, and then how he goes through his training program. But I'm well and truly expecting him back by the time finals start."

MEDICAL ROOM Check out the full injury list

Adding to Sydney's injury woes, key defender Will Edwards suffered a severe ankle fracture and dislocation in the final term. Edwards has since been discharged from hospital following Sunday's surgery, though he remains in Melbourne.

"He's in a better space," Cox said.

"I think the hardest part, with the severity of the injury, is having been through this a few times already. The reality's probably set in that it's a sustained stint on the sidelines. The first part was to look after him and get the surgery done.

"The continuous support and check-ins that we have with him and his family are really important. He's progressing well."

The setback is particularly unfortunate given that Edwards had solidified his spot in Sydney's backline during a breakout campaign, earning a three-year contract extension just days before the match.

"It's a cruel industry at times," Cox added.

"I think the part with Will is his ability to, first, commit to the football club. It's great for him and the footy club given what he's put in and what he's been through. Then to completely flip and do a 180, end up in hospital having surgery, and face another lengthy period on the sidelines — it's not ideal for anyone. He's been through a lot in his short footy career, but he's resilient, and he'll have to be through this period with the support of everyone around him."

Ironically, Sydney's match-winning last-quarter surge was sparked during the extended break while Edwards received medical attention.

"To the players' credit, the ability to be able to take a few messages, but also to settle themselves down after that horrific injury," Cox said.

"A lot of them saw Will on the ground, which wasn't ideal. From that, to be able to galvanise, work out what they wanted to focus on, and then execute — the part I was most pleased about, and said to the players all week, is we didn’t go away from what we know works. We stuck to the process, and the plan that we went in with, and we were able to execute it for longer."