Riding the crest of a wave following their group-stage heroics against Denmark, Australia meet South American champions Argentina in the last 16 of the World Cup on Saturday.

The Socceroos' second straight victory came in midweek, and coach Graham Arnold is surely loath to change a winning team. However, he could feel the need to alter his starting lineup a little, given a rapid turnaround in-between games.

Beating the Danes 1-0 at Al Janoub Stadium saw centre-back Harry Souttar and goalkeeper Mat Ryan again put on top-notch performances, and that pair will feature in a relatively settled defensive setup.

There is an ongoing battle to start at right-back, though, as Nathaniel Atkinson and Fran Karacic - who started the first and second games respectively - aim to usurp current incumbent Milos Degenek of Columbus Crew, who is one of five men at risk of a suspension for receiving a second booking at the finals.

Meanwhile, in midfield, Craig Goodwin was replaced by Keanu Baccus at half time versus Denmark, but an otherwise solid showing in Qatar should see the former keep his place alongside integral anchorman Aaron Mooy in the Aussies' engine room.

Riley McGree's superb display last time out is set to earn the Middlesbrough man another start in support of target man Mitchell Duke, who leads the line up front; Jamie Maclaren provides an able deputy on the bench.

As Hellas Verona's Ajdin Hrustic has been restricted by injury so far, he may once more be consigned to a substitute role, most likely taking a seat alongside Awer Mabil and Bailey Wright, both of whom are contenders for inclusion should Arnold opt for a more radical reshuffle to tackle the might of Messi's Argentina.

Australia possible starting lineup: Ryan; Karacic, Souttar, Rowles, Behich; Mooy; Leckie, Irvine, McGree, Goodwin; Duke

> Click here to see how Argentina could line up for this last-16 contest