ADAM Goodes is fighting an uphill battle to be at his best for the Sydney Swans' upcoming finals campaign after it was announced he would undergo surgery on his right knee on Tuesday.

 

Goodes injured his knee against Port Adelaide 10 days ago and it was initially thought he would only miss one week, but the cartilage damage he sustained hasn't recovered as the club's medical staff had hoped.

 

The decision has now been made for the 33-year-old to undergo surgery, which will rule him out for at least six weeks.

 

Coach John Longmire said on Monday a return in round 21 or 22 would be the "best-case scenario" for the Swans' games record-holder.

 

That would then leave just the round 23 showdown with Hawthorn as potentially his final hit-out before the finals.

 

The Swans were forced to cope without Goodes for six weeks due to a torn quad last year and when he returned, the dual Brownlow medallist put in one of his poorest performances in recent memory.

 

Showing understandable rust, Goodes was ultimately subbed out of his comeback game against Geelong, and took some weeks to recapture his best form.

 

Having recovered from an injury to his other knee in last year's Grand Final, Goodes had been excellent once again this season, underlined by his stunning display against Collingwood in round nine.

 

But the Swans must now accept the fact they will have to continue their push for a top-four finish and the best shot at back-to-back flags largely without their superstar.

 

"Last year we were pretty competitive with him out and at some point in your evolution as a footy team, you've got to make sure you can cover some of the star players that have carried the load for a long time," Longmire said.

 

"Adam has certainly been a star of this footy club for a long time and it's been good to see the development of other players.

 

"We've seen (Jarrad) McVeigh and Kieren Jack, Ryan O'Keefe, Jude Bolton take their games to another level.

 

"Our younger group coming up underneath that have been good as well.

 

"The balance of the team has meant that if an Adam Goodes misses we can still be competitive and that's what it needs to be.

 

"We can't rely on Adam Goodes to win us games of footy and clearly over the next six weeks, that won't be the case."

 

Goodes appears to be remaining upbeat, seen limping but still smiling and waving to passersby outside the SCG shortly after Longmire's press conference.

 

But the Goodes news caps a wretched injury run for the Swans, who were missing nine members of the 2012 premiership side in Friday night's win over Carlton.

 

Lewis Jetta (shin) will miss Sunday's trip to the MCG to face Melbourne, a worrying fifth straight week out for the speedster.

 

There was at least some positive news, however, with Sam Reid (quad) and Shane Mumford (cheekbone) pushing for a recall to face the Demons.

 

Longmire was doing his best to remain upbeat about his casualty ward.

 

"Six months after you play in a Grand Final, you don't expect nine players to be out of your Grand Final team, so that's been a bit of a challenge," he said.

 

"But that's also provided some magnificent opportunities for players.

 

"We may not have seen what Dane Rampe's able to do or seen Jed Lamb play his first game or Brandon Jack.

 

"Those players have come into the team and shown us they've got a bit of a future and at the same time contributed to us winning on the weekend."

 

Prior to last season, Goodes had enjoyed a charmed run with injury, appearing in at least 20 games in each of his first 13 seasons in the AFL.

 

Longmire wasn't sure if he was finally showing signs of age or wear and tear, or if it was just bad luck.

 

"It's hard to know. These things happen. Sometimes you have a really good run and he's had a good run for a long, long, long time," he said.

 

"And you go through a year or two where you don't get a good run, both as individuals and as a team I guess.

 

"He's been blessed up to this point, but he's having a bit of a tough trot."