A bonus-point loss or a tight defeat by England should be enough for the Wallaroos to reach the quarter-finals of the World Cup but Chancellor wants her team to break the hosts' 29-game winning streak on Saturday.
"We're looking forward to the opportunity we have to cause the upset of the competition," she told reporters.
"If we say the last game was the game of the tournament, let's look for the upset of the tournament."
The Wallaroos' last game was a 31-31 draw against the United States, a team England smashed 69-7 before embarrassing Samoa 92-3 to reach the quarter-finals.
Australia have a 0-7 record against England and were belted 42-7 by the Red Roses in their last meeting nearly two years ago.
But flyhalf Tia Hinds is comfortable with Australia's underdog status.
"It's always great to be the (dark) horse, you know, the pressure isn't on us," she said.
"The pressure is on England and there's really nothing for us to lose in this game.
"They're not unbeatable - history says they've been beaten before - and it doesn't say we can't do that."