The Danes, who finished second in Group D, will be looking to spoil the party and eliminate the tournament co-hosts.
Match preview
After beginning the tournament with a narrow 1-0 win, Australia suffered a surprise 3-2 defeat to Nigeria in their second group game, leaving them in third place and at risk of an early exit.
Despite having the added pressure of being the Women's World Cup co-hosts, Australia saved their best performance for their final group match, as they brushed aside the Olympic Champions Canada.
Hayley Raso's first-half brace put the Matildas in control, before Mary Fowler added a third just before the hour mark.
Steph Catley dispatched a stoppage-time penalty to round off a dominant 4-0 win, sealing Australia's place in the knockout rounds and condemning Canada to a group-stage exit.
After finishing as group winners, Australia set up a last-16 tie with Denmark, and they will be hoping to draw inspiration from their previous meeting with the Danes in October 2022 when the Matildas came from behind to claim a 3-1 win in the friendly encounter.
Denmark, meanwhile, got their campaign up and running with a narrow win over China, before they were stopped in their tracks by England on Matchday Two.
After being edged out being the European champions, Denmark picked themselves up to win 2-0 in their final group game against Haiti.
Pernille Harder opened the scoring from the penalty spot, before Sanne Troelsgaard came off the bench to add a second goal deep into stoppage time, sealing all three points and securing Denmark's spot in the last-16.
Denmark, who are appearing in their first Women's World Cup since 2007, now have the chance to record their first win in the knockout stages of the tournament.
While they may have lost their most recent meeting with Australia, they managed to beat the Matildas 3-2 when the two nations met in a friendly in June 2021.
Australia Women Women's World Cup form:
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Denmark Women Women's World Cup form:
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Team News
After cruising to a comfortable win over Canada in their final group game, Australia boss Tony Gustavsson may be tempted to select an unchanged side.
Fowler marked her return to the starting lineup with a goal, and the Manchester City forward is set to start in a forward pairing alongside Emily van Egmond.
Sam Kerr has missed the group stage with a calf problem, but Australia's star striker could be fit enough to play a role off the bench in Monday's contest.
As for Denmark, Stine Pedersen could be brought back into the starting XI after dropping down to the bench for the win over Haiti.
Josefine Hasbo could also return to the side for the last-16 tie, and she is likely to feature in a midfield three alongside Karen Holmgaard and Kathrine Kuhl.
After opening her account for the tournament on Tuesday, Harder will be looking to add to her tally when she leads the line against Australia.
Australia Women possible starting lineup:
Arnold; Carpenter, Hunt, Kennedy, Catley; Raso, Gorry, Cooney-Cross, Foord; Van Egmond, Fowler
Denmark Women possible starting lineup:
Christensen; Sevecke, Pedersen, Boye, Veje; Hasbo, Holmgaard, Kuhl; Thomsen, Madsen, Harder