The veteran forward will have a scan on Thursday to determine the extent of the injury to his right hamstring.

But whatever the damage, Sydney will take a cautious approach with the eight-time All-Australian given he is in his 16th AFL season and is coming off a injury-riddled 2019.

The 33-year-old also missed the Swans' opening round win over Adelaide before the season was suspended in March.

Franklin played his 300th AFL game in the final round of 2019, after his return from a nine-match absence due to ongoing issues with his left hamstring.

He took to the field just 10 times last year - the least amount of games the four-time Coleman medallist has managed in a season during a career that started in 2005.

Franklin is in the seventh season of a monster nine-year, $10 million deal which saw him leave Hawthorn for the Harbour City at the end of 2013.

He is yet to rejoin the club's main training group as he was being eased back into drills following a knee arthroscopy in January.

"Lance hadn't been participating in contact training this week as we have been gradually building his training load," Swans football manager Charlie Gardiner said.

"He was doing some routine running drills at Lakeside Oval this morning when he experienced pain in his hamstring, which is clearly a concern.

"It's a disappointing setback for Lance as he had been progressing well in his preparation for round two."

Franklin needs 56 more goals to join Tony Lockett, Gordon Coventry, Jason Dunstall, Doug Wade and Gary Ablett Snr in becoming the sixth player in VFL/AFL history to reach the magical 1000-goal mark.

Earlier on Wednesday, ace Swans defender Dane Rampe said the two-month layoff had been beneficial for Franklin and he was tracking well.

"We'll be ramping him up ... he should be in full training on Friday and then hopefully get a few games in him as soon as possible," Rampe told SEN.

It's another blow for the Swans, who have ruled key tall Sam Reid (calf) out of their clash with Essendon at the SCG on June 14.

Australian Associated Press