GEELONG could give Mark Blicavs the enormous job on Sydney Swans star Lance Franklin if Tom Lonergan is ruled out of Thursday night's clash at the SCG due to concussion.

Lonergan suffered a knock to the head during the first quarter of the Cats' win over North Melbourne at Simonds Stadium on Friday night.

He is considered unlikely to take on the Swans, although his teammates are hoping that he will be fit to play, especially as his record against Franklin is excellent.

"I'm pretty sure he'll get up," midfielder Mathew Stokes said on Monday morning. 

"You never know with 'Domsy'. He's a strange cat.

"We need him this week. It's a big test for the backline players with the firepower they have up there.

"He does play well against Buddy … so it would be a big out if we do miss him."

Blicavs emerged as a key defensive prospect against the Kangaroos after being subbed into the game in place of Lonergan.

The mobile big man spent most of him time in the backline, where he often picked up Majak Daw.

Now Stokes has backed him in for the huge task of quelling Franklin.

"We're happy for him to fill the void if 'Domsy' doesn't get up," Stokes said. "I think it's all about challenging the young players.

"'Blitz' is a very talented young player, so if it happened to be that way, then we'd have to back him in and the back the rest of the team defence to help him out."

Geelong has plenty of other options for Franklin if Lonergan is ruled out and Harry Taylor is given the job on Tippett.

Andrew Mackie has played on Franklin before, while Jared Rivers is another tall defender who is in good form, although he might have to play on Sam Reid.

Draftee Jake Kolodjashnij has also been pressing his case in the VFL.

"Jake's still a pretty young kid," Stokes said. "We're pretty happy with where he's at but whether he's up to playing against the Sydney Swans in Sydney, against Kurt Tippett and Buddy Franklin, I'm not sure."

The Cats have won 12 of their past 14 games against the Swans but the Sydney-siders have really hit their straps in recent weeks.

"So it's a really good test for us to see exactly where we're at," Stokes said.

"It is a long year, and you don't win the flag by playing good footy at the moment but it's all about improving.

"I think we took a couple of steps backwards a few weeks ago and we've spoken about it as a team, and I think we improved on Friday night. But we can still get a lot better."

Geelong will wear a special Indigenous Round jumper on Thursday night.

The guernsey was designed by talented local indigenous footballer and artist BJ O'Toole, who Stokes has worked closely with in recent years.

"It's going to be great running out in that jumper," Stokes said. "We had a few designs that we looked at as a playing group and every single person in the room wanted that one.

"And the story with it is significant, too. It's about all the Aboriginal players from around Australia coming to Geelong and visiting the people here and then going away and going back home.

"I'm a bit biased, but I think it's the best jumper in the AFL."

Twitter: @AFL_AdamMcNicol