CHAD Cornes concedes his career may be over as the Greater Western Sydney veteran battles to overcome a chronic knee injury.

Cornes played 16 games last season after being thrown a lifeline by the Giants, taking his career tally to 255 games, but he hasn't been able to play a game this year after undergoing knee surgery in the pre-season.

Cornes was at a function in Sydney on Friday to celebrate brother Kane's club-record 256th game for Port Adelaide against GWS this Sunday and said he has accepted he may not play again.

"It's not completely over, there's still a little bit of a chance there, but yeah, I have got my head around it," Chad said.

"Last year for me was just a real bonus, I got out there and got to play with a great young group of kids and got given the chance by GWS to extend my career.

"I've loved that side of it and now it's time to do something else and move on to the coaching side of things.

"My knee's just not coming along as I would hope.

"I'm still pushing forward with rehab, but time is starting to run out, so I'm not sure if I'll get back by the end of the year.

"But I'll keep having a crack and see where it ends up.

"I was hoping to get back by the middle of the year, it's the middle of the year now and I'm not seeing any real improvement with my knee.

"It's a shame, but I'm putting my focus in to try to help out with the coaching and help these young kids, which I'm really enjoying."

His brother Kane passes Warren Tredrea's club-record tally on Sunday and revealed he won't be in the running to become the first Power player to bring up 300 games.

The 30-year-old feels he only has one more season left in him.

"I'd love to play maybe one more next year and that might do me," he said.

"It's probably time to do something else.

"I've had a really good run with footy and I've loved it, I'd love to go one more, and that'd be enough."

Sunday's clash is the first between the sides at Skoda Stadium since GWS stunned Port with a 34-point win in round 19 last year, the Giants' sole victory at their Sydney home to date.

That game also spelled the end of Matthew Primus' coaching tenure at Port and led to a total revamp of the South Australian club.

Chad Cornes, who played that day against his old club, said he doesn't rub his brother's face in that defeat, which rocked the Power.

"It's a pretty sore topic that one," Chad said.

"I don't like to bring it up too often. But it was a great moment for our club and it was a big turning point for Port.

"In the end it's probably been a good thing for them if you look where they are now and the people they've got in charge now and they're really going in the right direction." 

GWS coach Kevin Sheedy said Cornes' absence this season has significantly hindered his side.

"That's disappointing if he doesn’t (play again) because he's just been a marvellous player to get in the short time we've had him," Sheedy said.

"He's probably one of the main reasons why we haven't won two or three games already."

James Dampney is a reporter for AFL.com.au. Follow him on Twitter: @AFL_JD