"If they smash us in the tackles they'll beat us," Roos said matter-of-factly at his pre-match press conference at ANZ Stadium on Thursday.
Against Collingwood in last year's elimination final, the stats sheet showed that Collingwood laid on more than twice the tackles of Roos' men as the Swans went down by 38 points.
If that trend continues, the Swans will be staring down the barrel of a fifth consecutive defeat against the Pies.
"We talk about tackling on a weekly basis but going into this game we're aware of the stats in the last three games [against Collingwood in 2007].
"And if they [Collingwood] do that again, they'll win, regardless. The guys need to come in with the mindset to compete really, really hard."
Roos added that when the Magpies beat the Swans in last year's elimination final Collingwood were on the way up and, going by ladder position, "we were on the way down."
Quizzed on whether those roles are now reversed Roos was non-committal.
"We're playing good footy and against Geelong, Collingwood played the best game of footy I've seen this year.
Collingwood thumped the reigning premiers by 86 points in round nine, Geelong's only loss so far this season.
"I think they had 80-something tackles against Geelong," noted Roos.
"And because they're a good kicking team, if you're not able to put pressure on them they're able to get the ball to their forward line quite quickly because they do kick the ball well.
"It gets back to pressure. If we don't put pressure on the ball carrier, they'll beat us like they have the last three times."
Roos said there was no extra motivation to beat the side that dumped them out of the finals.
"You don't get four-and-a-half points for beating Collingwood. We're probably softened to all that [anti-Collingwood sentiment] up here in Sydney.
"We just need to play better than we did last year against Collingwood in the final. And the players are aware of it. We got beaten and our season ended because of Collingwood."
