While the Socceroos will be relying on France to win comfortably against Denmark, a victory over Peru is essential if we are to progress to the Round of 16.
Based on the Aussies' second half performance against the Danes, this ideal scenario looks well within the realms of possibility.
But if one thing is certain, it's that Peru will be giving everything to win themselves.
Even though Los Incas's two losses mean that they have no hope of progressing in the tournament, they will be determined to notch-up a win in their first World Cup appearance in 36 years. With such a long absence, there's no way in the world that the proud Peruvians will simply play to make up the numbers tonight.
In their two group games so far, Peru have looked very dangerous going forward, despite failing to find the back of the net. They missed a penalty in their first game against Denmark and were unlucky when hitting the post against France.
There's a definite sense that a Peruvian goal or two is just around the corner.
With Peru set to go for the win, this could play right into Australia's hands, in what is expected to be a much more open and high-scoring game.
Australia will need to be wary of Peru's pace and skill, especially from their full backs who like to get forward. Left-back Miguel Trauco in particular has had a promising tournament, backing up his club form for Brazilian giants Flamengo.
The line-ups
Both nations have a player ruled out with injury.
Peru lose inspirational winger Jefferson Farfan, while Australia will have to cope without the hard running of Andrew Nabbout up top.
While there are clamours for Tim Cahill to start, van Marwijk will likely play the younger and more mobile Tomi Juric or Jamie Maclaren, before bringing Cahill on with 20 minutes to play.
Robbie Kruse's position is under threat with many tipping Daniel Arzani- the youngest player at this World Cup- to start in his place. In the 25 minutes he was on the park against Denmark, Arzani had 2 shot assists, 1 shot on target and completed 2 out of 3 take-ons, demonstrating attacking proficiency which the Aussies have been yearning for.
A key for Peru is whether talented midfielder Renato Tapia starts, after being ruled out with injury against the French. A very direct player who always looks to move the ball forward, Tapia had a great game against Denmark, where he played 35% of his passes in a forward direction.
Contrast this number with Mooy and Jedinak's figures against the Danes, where they only played 25% and 28% of their passes forward respectively.
Key stats and players
Peru's attacking threat is underscored by the stats. In their two games to date, Peru have had 27 shots at goal, 8 of which have been on target.
Compare this with the Socceroos, who against the same opposition, have only had 19 shots at goal, 5 of which have been on target. As two of these shots on target have come from penalties, the numbers suggest that the Socceroos struggle to create chances from open play.
In fact, the last World Cup goal that Australia scored from open play was Tim Cahill's wonder volley against the Netherlands in the 21st minute of their second game in 2014.
Australia
With all of our number nines as well as Robbie Kruse and Tom Rogic not presenting a genuine goal threat, Mathew Leckie again looks like Australia's main route to goal.
Leckie has been superb in his two games in Russia, providing plenty of speed as well as muscle on the right wing.
With 7 shots at goal already (more than any other Socceroo), Leckie just needs to improve his finishing to find his name on the score sheet.
Peru
Los Incas' captain Paolo Guerrero didn't even think he would be playing at this World Cup, after a twelve-month ban for testing positive to cocaine initially ruled him out.
However, after all the group C captains including our very own Mile Jedinak petitioned for him to play, the ban was over-turned.
Hopefully, Jedinak won't be regretting this act of generosity after tonight's game, with Guerrero looking particularly dangerous in front of goal for Peru.
Three of his five shots have been on target, and his class and experience might just prove the difference in this clash.
Key Match-Up
Andre Carrillo vs Aziz Behich
Peru's right winger Carrillo is Peru's main weapon in attack. Fleet of foot and with a bag of tricks, Carrillo has successfully completed 8 out of 12 take-ons in Russia.
In this clash, he'll be running at Australia's left-back Behich, who will need to be defensively superb to repel him.
So far in Russia, Behich has won 7 out of 16 duels with opponents. This number suggests that Carrillo will get the better of him, unless he lifts his game to a new level.
Betting Tip
Peru to win head-to-head @ $2.35.
As much as the Socceroos need and want to win, Peru just look to be a class above in the final third.
It's hard to see them going home without scoring a few World Cup goals.