The 23-year-old suffered the injury during Friday night's semi-final win over Greater Western Sydney and was subbed out of the match at the end of the opening quarter.
The Geelong utility has battled a history of hamstring setbacks, with Fox Sports' Tom Morris revealing the Northern Territory product's season has ended abruptly.
Brandan Parfitt's scans are back and it's not good. He's out for the season with a hamstring, even if the Cats make the GF. @FOXFOOTY
— Tom Morris (@tommorris32) September 6, 2021
“It’s a hamstring that didn’t look good. I think you can join the dots a little bit that it’s not a minor hamstring,” Scott said.
Parfitt joins defensive duo Tom Stewart (Lisfranc) and Mark O'Connor (hamstring) in the Cats' casualty ward, with the latter pair unlikely to return to to Scott's side this post-season.
Stewart has flagged he will continue his push to make a stunning return from a substantial foot injury.
The Cats will face Melbourne at Optus Stadium on Friday night for a place in the 2021 AFL Grand Final.