SYDNEY superstar Lance Franklin enhanced his reputation as a "massive competitor" on Saturday night, fighting on after a knee knock in the opening minutes against Fremantle to boot three important goals in what could have been his last game in Perth. 

Franklin was the headline act at Optus Stadium as mystery surrounds his future beyond this season, but the champion forward was forced from the ground early in a crunch game for the Swans. 

After returning and playing a crucial role, particularly through his two goals in a tense third quarter, coach John Longmire was full of admiration for the 36-year-old's fighting effort. 

DOCKERS v SWANS Full match coverage and stats

"There's moments tonight, he just stood up and did what he had to do and imposed himself. He's just such a massive competitor still at 36 to be able to do what he does," Longmire said. 

"He's got a bit of a knock on his knee in the first five minutes, so he just came off at one stage and he just was a bit sore.

"But he got on a bike, he was like on the Tour de France there for a second and had the yellow jersey on and away he went just to get it warm. He bounced back fine. 

"So we'll see how it goes next week but he finished the game really strongly which is good." 

Asked about the prospect of Franklin having played his final game in Perth, Longmire said: "It's not fun for me to go down that path, but I thought he did OK today. I thought he played well."

The most pleasing aspect of the 29-point win for Longmire was the Swans' ability to hit back every time Fremantle looked like mounting a charge, with the Dockers' three unanswered goals either side of half-time their only run of multiple goals for the game. 

"That was a good sign. To be able to hold that momentum and counter punch back," the coach said. 

"We were highly engaged and emotionally tuned into the contest. Straight kicking was a factor in that first half and I thought we played pretty well.

"They obviously rolled the dice in the last quarter where we held up strong. It's always pleasing to come over here and get a win."

Fremantle coach Justin Longmuir was left frustrated by a 12-minute patch through the first quarter in which the Dockers conceded the five rapid goals that proved the difference in the match. 

"We need to get on top of that. You concede goals, it just can't be five in 12 minutes where you touch the ball 15 times and they touch it 45 times and you lose total control of the game," he said. 

"We need to get better at that. But I think we played a style of footy that'll hold us in a lot better stead going forward than what we have the last few weeks."

Longmuir was pleased with young star Luke Jackson's impact in the ruck, with the premiership big man stepping up in the absence of Sean Darcy to finish with a career-high 43 hitouts. 

"I thought he was good. I'll go back and have a look at it, but I thought he played his role well and competed in the air and at ground level. Then he got a bit of his mojo going around the ground as the game wore on," Longmuir said.

"We went with a different structure tonight than when Sean was missing last time and I thought Corbs (Josh Corbett) gave us a decent contest ahead of the ball when he had to and brought it to ground and created some opportunities himself as well.

"We'll keep tinkering with personnel but I think that structure is a better structure for us."

Longmuir said the 15th-placed Dockers remained invested in this season, despite finals now being out of reach, but would look to change aspects of their game. 

"This week we spent a fair bit of time and re-tooling our roles and our mindset, and we'll continue to do those sorts of things," he said.  

"As far as personnel goes, we'll just keep rewarding the guys in good form. They can't get much younger, so we'll just keep rewarding the guys in good form."