GEELONG is counting the cost of a bruising encounter against Fremantle at Simonds Stadium on Sunday, with captain Joel Selwood suffering another concussion and young defender Tom Stewart carted off to hospital with a facial fracture.

The Cats were down to one healthy player on the bench in the final term, with Darcy Lang (knee contusion) also hobbled, but held on to a gutsy two-point come-from-behind victory.

WATCH: The last two minutes

Cats coach Chris Scott was concerned about the injury to Stewart, who collided with the back of Fremantle opponent Hayden Crozier's head in a marking contest in the second quarter.

Stewart was sporting a sizeable bump above his right eye following the incident. 

"He's got a significant eye socket injury. He's gone to hospital. Not sure of the extent of the injury but the nature seems to be a facial fracture of some sort," Scott said.

Selwood was knocked out in the first 45 seconds of the match when he clashed heads with Dockers forward Hayden Ballantyne as both players attacked the ball in dispute in a contest inside 50.

The Cats captain lay motionless after the sickening collision as his teammates gestured towards the medical staff for a stretcher.

The stretcher came out onto the ground but Selwood shrugged that off and decided to walk off with the assistance of trainers.

As he got closer to the club's race, Selwood jogged off the ground to receive further treatment inside the club's changerooms.

"I wasn't surprised to see him run off. It was probably a message to our medical staff and our fans, and the coaching staff as well," Scott said with half a smile.

"The decision was made relatively quickly. Often these things take the full 20 minutes or however long the procedure takes to work through.

"I can't give you an outlook on the positive or negative side but I will say we're really confident that he'll work through a stringent process which will give us an outcome independent of the coaches, players and administration.

"To try to give you something, he was up and about really quickly and he was talking to me about how the game was going on – which is a good sign.

"He certainly wasn't in such a state where he couldn't speak to his teammates and coaches coherently."

WATCH: Chris Scott's full post-match media conference

With the Cats facing a six-day break ahead of next Saturday night's clash against Greater Western Sydney at Spotless Stadium, Selwood appears to be in great doubt, although Geelong was refusing to rule him out at this early stage.

The fact Selwood has had a history of head knocks would suggest Geelong will be extremely cautious with his recovery.

Lang ran into the knee of Fremantle opponent Lachie Neale at the start of the third quarter and was forced from the ground with a noticeable limp.

The Cats sent him back out onto the ground but he was clearly limited, meaning he too was done for the day halfway through the third term.

Lang remains a chance to face the Giants.

Joel Selwood was carried off the field by trainers before jogging off himself. Picture: AFL Photos