Coach Lionel Scaloni insisted FIFA World Cup 2022 giants Argentina would not be taking outsiders Australia lightly having already had their fingers burnt by Saudi Arabia earlier in the tournament.

Argentina's World Cup hopes were hanging by a thread after they were shocked 2-1 by the Saudis in their opening Group C match.

However they bounced back in impressive style to beat both Mexico and Poland 2-0 and top the group, setting up a last 16 clash with the Socceroos.

"They're all difficult, we saw that with Saudi Arabia," Scaloni told reporters late on Wednesday.

"If you think Australia will be easy you're wrong because they have shown that getting through against tough teams in this World Cup."

Scaloni admitted he and his backroom staff had spent little time analysing Australia so far but would do so now.

However he insisted that while "we have to analyse our opponents, we have to also think about how to hurt them."

Scaloni also hit out at organisers as Argentina will play their last 16 tie on Saturday with only two full days to rest.

"We are happy today but I don't want to be euphoric because I think it's crazy that we're playing in just over two days despite being winners of this group," he said.

"I can't understand it. It's already (the early hours of) Thursday and we have two days and then we have to play it."

Scaloni dismissed suggestions that Argentina's defeat to Saudi Arabia had been a blessing in disguise.

"No, I don't think it was beneficial to lose, we didn't gain anything from that defeat and we knew we had to win the remaining two games."

For the players, Argentina's ability to bounce back from that adversity showed their mettle.

They even overcame captain and talisman Lionel Messi missing a first half penalty with the score at 0-0.

"We showed we have a lot of character and personality. We deserve respect for finishing first in the group and the way we played," said midfielder Rodrigo De Paul.

Centre-back Nicolas Otamendi added: "We're a team that gets stronger under pressure, we keeping demonstrating it."

Midfielder Alexis Mac Allister, who opened the scoring less than a minute into the second half, said it was a "dream come true" to bag a goal at the World Cup.

And he insisted the team never stopped believing, even after Messi's miss.

"We were always positive, we had the composure we needed to win this match -- the missed penalty didn't get us down," he said.

Maradona would be 'super happy': Messi

Lionel Messi believes Diego Maradona would be "super happy" after he led Argentina into the World Cup last 16.

Messi became his country's most capped player at the tournament with a 22nd appearance surpassing his legendary compatriot who died just over two years ago.

"I learned it recently, I didn't know it. It's a pleasure to be able to continue to achieve these kinds of records. I think Diego would be super happy for me, because he always showed me a lot of affection, he was always happy when things went well for me," said Messi.

Despite missing a penalty – his 39th career failure from the spot – the Argentina captain said he was "happy" with this "big match".

"We achieved our first objective, which was to get out of the group after starting the way we did (a shock 2-1 loss against Saudi Arabia)," said Messi.

"I was really frustrated to have missed the penalty, because I knew that a goal could change the whole match, that it makes you play in a different way. But I think that from the penalty I missed, the team came out stronger."

Messi, who still needs a World Cup winner's medal to cement his legacy as one of the sport's greatest players, believes Argentina are moving up through the gears at precisely the right time.

"After the first goal, everything went our way. We started doing again what we had been trying to do since the start of the World Cup, but which we hadn't been able to achieve for various reasons.

"Having been able to do it today, it gives us confidence for the future."