ST KILDA captain Jack Steele is expected to be sidelined for between six and eight weeks after scans confirmed he would require surgery following a right shoulder injury on Saturday night.

Steele left the ground in the second term of St Kilda's 10-point win over Geelong after being grounded in a tackle by Jake Kolodjashnij.

Steele returned soon after following medical treatment and played out the game, finishing with 22 disposals.

Scans on Sunday confirmed a rupture to the 26-year-old's right AC joint.

"Jack's a really tough guy and playing on last night despite his injury is evidence of that," head of football David Rath said.

"It's really disappointing to have Jack out for an extended period of time, but it's important for him to get the treatment he needs to set him up for the second half of the season.

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"He's a warrior and would continue to play if required, but we need to do what's right for Jack long-term.

"Jack's a pro on and off the field and will no doubt attack his rehab professionally, which will hopefully see him back playing as soon as possible."

Speaking after the win on Saturday night, coach Brett Ratten praised Steele for returning to the field.

"The thing with Steele at half-time, you're walking down thinking, 'gee, we could be in a bit of trouble here', but he's courageous," Ratten said.

"I think a bit of 'Gears' (former captain Jarryn Geary) is rubbing off on him, because he just willed himself to get out there and compete and just make contests. It helped us with the rotations. I'm not sure where that AC (joint) will be next week, but we'll just work that out.

"We'll get some scans and things and see. He finds a way, Jack, he wills himself and it's a credit to him."

Ratten clarified small forward Jack Higgins' concussion – his second for the season – occurred in the first term, but that he didn't feel symptoms until the second.

"He asked the doc, and the docs did the scan, and he failed that, so we took him out. He'll miss another game, and we'll look after him," he said.

"We didn't know, he got up, and then didn't feel right until the second. Maybe [the incident] was the (Tom) Stewart spoil, the big spoil, I think (Ben) Long might have kicked it in."

Veteran ruckman Paddy Ryder turned back the clock with a match-winning display, including two goals in the fourth quarter.

"Ryder's influence was enormous. His dad is over from Western Australia, so I did say to him post-game, 'can he come every week?', because that was brilliant," Ratten said.

"He's played some patches this year, but the performance this year – three goals and some of his ruck work – we know what he can do with hitouts and giving our players first access to the ball, and it was a really good display."

Geelong coach Chris Scott said contested footy was his side's biggest issue on Saturday night, but wasn't overplaying the loss.

"(The third quarter) was obviously where the game was won by them, they did take it away from us, and we clearly just didn't play well enough in that period. It is a shame, because for the most part, we probably have control of the game if you take out that 20-minute patch," Scott said.

"Even the contested ball numbers, we were down 14 for that quarter and we were down 14 for the game. So that patch is clearly something we'll focus on. There were things that hit us in the face that we're aware of already and the players are aware of, and we just couldn’t get the game played the way we needed to in that patch.

"There were periods as well – we were so dominant in that second quarter and just couldn't get a wider buffer. And we certainly had our chances – even four posters – we just aren't good enough right at the moment that when we take control of games, that we can take it completely away from the opposition. I think we'd be entitled to think we had an opportunity to do that."

Scott heaped praise on young defender Sam De Koning, who was locked in an enthralling battle with fellow rising star Max King.

"He's been a real positive for us. St Kilda play this venue well, and they certainly saw the opportunity to stretch us a little bit, in the conditions," Scott said.

"So Sam became even more important then, because we only really had the one tall defender.

"He's probably the best young key forward in the comp, Max King. Hopefully, what you're seeing a little bit is Wayne Carey-Glen Jakovich type stuff. That would be nice, wouldn't it?"

Scott said Rhys Stanley spent some time off the field getting his ankle strapped, and there were some "awkward" minor injury moments in the first and third terms, but Jed Bews (concussion) should return next week.