IN-FORM Sydney Swans midfielder Jude Bolton has received positive news on his injured knee, but the veteran is still likely to miss Sunday's crucial clash against Fremantle at the SCG.

Bolton was a late withdrawal from Saturday's 70-point win over Gold Coast, hyper-extending his knee while kicking in the warm-up and being replaced by emergency Luke Parker.

Scans on Monday showed the 31-year-old only has some slight bone bruising and no structural damage, but is still likely to need another week on the sideline to fully recover.

"His knee's still a little bit sore so he's no certainty to play this week," Swans coach John Longmire said.

"At 31 your knees aren't going to be like what they were like at 21, but he was ready to play and trained last Thursday.

"We went into the game fully expecting him to play."

Bolton's sensational season has seen his name often brought up in All Australian discussions.

Longmire is expecting Bolton to miss another week, although the coach admits it's not easy keeping the tough-tackling midfielder in the stands.

"It's always hard to stop Jude Bolton playing," Longmire said.

"I thought when he pulled out in the warm-up he might have had a broken leg and I was expecting when the scan came back today [to see that] his leg was actually broken.

"Fortunately it was actually good news and he may only miss one more at the most.

"It will be tough for him to sit in the stands again. I wouldn't want to be his wife, his wife mustn't be too happy with him when he's in this sort of mood and missing games.

"He hasn't missed too many over the years, which has been good."

While Longmire would be disappointed to lose one of his midfield generals for another week, he was thrilled with Parker's contribution.

The first-year Swan finished with 26 possessions, seven marks and two goals.

"I thought [Parker] was fantastic," Longmire said.

"We may give him another opportunity if Jude misses again."

Following three straight defeats, which had jeopardised their top-eight spot, Longmire was pleased with the effort against the Suns.

The Swans prevailed 15.16 (106) to 4.12 (36), holding Gold Coast to its lowest score of the season.

"We thought the defensive side of the game was pretty strong," Longmire said.

"They did kick a few behinds which made it a little bit easier, but to keep them to four goals was a good result for us.

"Our back six played pretty well, but our pressure all over the ground we were pretty happy with.

"I think we had some really good contributors right across the 22, so that was good, but we have another big challenge this week against Fremantle.

"It's going to be a tough one."

The Swans also revealed young key position player Lewis Johnston picked up an ankle injury playing for the reserves on Saturday and will be sidelined for at least a week.

Johnston, who has played his first two games for the club this season after being drafted in 2008, injured ligaments at the front of his ankle and will undergo more tests to determine how long he will be unable to play.

The views in this article are those of the author and not necessarily of the clubs or the AFL