2 min: Argentina 0-0 Australia
Would love to say that this one has started a pace but it's very steady in the opening stanzas. Both sides feeling each other out with Argentina dominating possession.
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0 min: Argentina 0-0 Australia
The Aussies get us underway....queue huge roars from the stands.
Kick off moments away
Right settle in then all. Hopefully we're on for a good one here.
Jason Burt is on site
Give us your match predictions
The teams are in the tunnel
Great colours on show tonight. The Aussie yellow against the traditional blue and white of Argentina looks really really nice.
Anthems next. Two decent ones for my money.
Another important mention
One milestone that did slip my net ahead of this one is that it's Messi's 100th appearance as Argentina captain tonight.
Big night for Premier League players
The additions of Alexis Mac Allister and Julian Alvarez to this Argentina team in the match against Poland appeared to really work for Scaloni. The former takes a modicum of attacking pressure off Messi in between the lines, while Alvarez is a real poacher in and around the penalty the area.
They retain their places tonight. Will the affect be the same?
Update from down under
It's the crack of dawn in Australia but this suggests the whole country is watching
Here's a fun pre-match factoid for you all. Australia have played Argentina seven times in total but have only won once. That success came when the nations first met in 1988. Australia's forward on that occasion - Graham Arnold.
This is certainly an occasion when first-hand experience of beating the famous blue and white may come in handy.
The Aussies holding their own
In the face of raucous Argentine support, the Australian fans in attendance are doing their best to match them....ish.
Argentina and Australia will understandably be fully focused on tonight's proceedings but its worth reminding you all about what, or rather who, awaits the winner.
The Netherlands put in their best display of the tournament so far to beat the USA 3-1 in the first match of the last 16. They will face the winner of this one next Friday.
There is a feeling of something prophetic in the air this evening with arguably the greatest footballer of the last 30 years making his 1000th appearance on the day when the man widely considered to be the greatest player ever entered end-of-life care.
Read the latest on Pele's condition HERE.
The managers' views
Both sides play on short rest tonight having concluded their qualification on Wednesday. Both managers have had their say.
The GOAT (if you're anyone else) has landed
The real GOAT...if you're an Aussie
More than just attack
Argentina's star-studded attacking options will always make headlines but it's defensive rigidity that gives this team it's real edge.
Lionel Scaloni's team have given up only 11 shots in the tournament so far. That's fewer than any other side.
Keep that record up and there's no telling how high this side could go in Qatar.
'We have to alert to everything'
Australia's centre back Harry Souttar on the challenge of facing a side which boasts Lionel Messi in its ranks.
These photos were taken over an hour before kick off....
Will their enthusiasm maintain? My bet would be yes but my word supporting Argentina looks exhausting.
Tonight is Lionel Messi's 1000th professional appearance as he wins his 169th international cap on top of 778 games for Barcelona and 53 for his current side PSG.
Such milestones deserve a performance of equal stature. Can Messi oblige tonight?
Let us know your score prediction
Fancy and Argentina win or a historic Australia upset? Maybe a bore draw and penalty shootout is what you had in mind.
Whatever your thoughts of the winner, give us a score prediction below!
Team news - Australia
Graham Arnold makes one change from the side that beat Denmark 1-0 earlier this week with Aziz Behich coming in for Craig Goodwin.
Australia starting XI: Ryan, Degenek, Souttar, Rowles, Behich, Leckie, Mooy, Irvine, Baccus, McGree, Duke
Subs: Atkinson, Karacic, Tilio, Wright, Maclaren, Hrustic, Mabil, Redmayne, Devlin, Vukovic, Deng, Kuol, Goodwin, King, Cummings
Team news - Argentina
Julian Alvarez and Alexis Mac Allister retain their starting spots after good performances against Poland in the final group game. Lautaro Martinez has to settle for a place among the substitutes.
Argentina starting XI: Damian Martinez, Molina, Romero, Otamendi, Acuna, De Paul, Fernandez, Mac Allister, Gomez, Messi, Alvarez
Subs: Armani, Foyth, Tagliafico, Montiel, Paredes, Pezzella, Di Maria, Rulli, Palacios, Correa, Almada, Rodriguez, Dybala,
Welcome to the Messi show
Welcome to the Ahmad bin Ali Stadium for the last 16 clash between Argentina and Australia - the latest event to play host to the Lionel Messi show.
From scoring a vital goal to break the deadlock against Mexico to missing a penalty against Poland, the greatest player of his generation has already generated copious headlines - both good and bad - but things are about to go up a notch.
Knockout football is where the truly great players show their worth and Messi will know, whatever the result here this evening, ultimate responsibility for Argentina's fate will be placed on his shoulders.
One real positive for him and his posse is that they appear to be cresting just at the right time. An opening round loss to Saudi Arabia put them on the back foot but convincing 2-0 wins against both Poland and Mexico have righted the ship for one of this tournament's big favourites.
Manager Lionel Scaloni may well have stumbled on something with the selections of Alexis Mac Allister and Julian Alvarez against Poland. Both appeared to take the load off Messi somewhat in the final third, allowing their talisman to roam more freely between the lines.
Argentina are prohibitive favourites for this one - understandable given the array of world-class talent they have at their disposal - but their opponents tonight will be a tough but to crack.
If Graham Arnold's Australia side have shown anything at this tournament it's that their brand of dogged pragmatism can cause problems for any side they come up against.
Harry Souttar, Mat Ryan and Aaron Mooy give the Aussies the sort of hard-working spine needed, at the very least, if they want to trouble a top side like Argentina.
Is there a gulf in class? Yes. But if this World Cup has taught us anything so far it's that any presumption or proclamation of certainly can quickly be made to look rather silly.