Roos says coach John Longmire and his support staff must make ruthless calls on some players - and change their game plan - for the club to recover from two grand final maulings in three seasons.
"The reality is if you can't get over the negativity of grand final day ... you have to leave," Roos told an ABC podcast on Monday.
"You have to get rid of those players.
"And as brutal as that sounds ... if John and the coaching staff firmly believe that there's players in there that can't perform on the biggest stage, you have to get rid of them.
"It's a brutal industry but that is just the reality ... if it is real, which potentially it is, you have to do something about it."
The Swans lost Saturday's grand final to the Brisbane Lions by 60 points, after losing the 2022 premiership decider to Geelong by 81 points.
Roos, who coached Sydney to the 2005 flag before handing over to Longmire at the end of 2010, didn't name any players to put up for trade.
But during his tenure, he had similar conversations with Sydney's leadership group after a finals failure.
Swans coach John Longmire (C) looks on during the medal presentation at the MCG. (Joel Carrett/AAP PHOTOS)
"I can't remember what year it was ... we met with the leadership group after the finals series and said: 'Guys, we're going to have to make some changes. And for us to get back to where we want to get to, we need to trade, we need to put people on the market'," Roos said.
"And the leadership group were fantastic and they knew it was going to be someone inside that room and they all agreed unanimously.
" ... And it turned out to be Jude (Bolton) that had the most interest but we couldn't get enough for him to warrant trading him.
"That has to take to place, that conversation now has to take place. They have to put good players on the market to change the narrative.
"There's no question the talent in terms of the management, their structure and the football club is there. But it's two (grand final losses) in three years with largely the same group.
"And there are some holes in the organisation in terms of game plan and now potentially personnel."
Roos said there were "absolutely concerns" about the Swans' game style.
"We're talking about a team that finished on top, we're talking about a team that played the grand final, so we're not talking about a bad football team," he said.
"But ... some of the patterns we saw this year, I think they lost 16 first quarters, they were really easy to score against in games, they would win games in the back-end of the season on the back of a good quarter of football.
"So they're trends. That is the concern.
"They weren't able to turn the game around because Brisbane just kept on playing hard, tough, physical, well-structured football and Sydney just couldn't respond.
"There's absolutely concerns for the Swans. They have dramatically changed their game plan this year.
"They are no longer a hard, tough, defensive team that is hard to score against.
"They are a team that is hard to beat because they're so talented but they're not hard to play against."
10°C