The dust has settled.

Bert van Marwijk’s tenure with the Australian national team has ended.

The Socceroos have scattered across the globe.

Some are sunning themselves on the beaches of Mediterranean Europe. Some are living it up in the United States. Some are relaxing with family in Australia.

But for incoming coach Graham Arnold, the planning has already started.

In just over six months, the Australian national team fly to the United Arab Emirates to defend their Asian Cup crown.

Between now and January 6, when the Socceroos begin the continental tournament against Jordan, the team will play just a handful of friendlies.

Despite the absence of playing opportunities, Arnold must quickly resolve some of the questions thrown up by the World Cup.

Who stays and who goes?

There is a real chance that when the Socceroos line up at the Hazza bin Zayed Stadium in Al Ain, they will be without three national team stalwarts.

Mark Milligan is believed to be set on retirement from international football, after a decorated career with the Socceroos.

Tim Cahill – just two caps away from equalling Mark Schwarzer’s all-time appearance record for Australia – is 38 and club-less.

And Mile Jedinak, although a star performer in Russia for the Socceroos, is approaching his 34th birthday and has had injury woes in recent years.

Even if Cahill and Jedinak do not step down from the national team, Arnold will need to contemplate how much longer they retain a place in the squad.

Cahill had a largely symbolic role in Russia, second-half substitution against Peru notwithstanding.

Will he continue to warrant a place, at the expense of younger players, if his playing role is to be no more than minimal?

The departure of any of these players will see a significant loss of experience in the national team, a concern ahead of a major international tournament.

How Arnold regenerates the Socceroos team while retaining that institutional knowledge remains an open question.

What style is best?

Arnold has a blank slate upon which to imposes his vision for the Australian national team.

He could continue in the footsteps of Ange Postecoglou, with the manager’s preference for expansive, passing-based football.

Or he could maintain the van Marwijk method, a pragmatic, reactionary approach with two defensive midfielders anchoring play.

The problem for Arnold is the variable standard of teams the Socceroos will face at the Asian Cup.

Australia has been drawn against Syria, Palestine and Jordan in Group B.

While Jordan beat the Socceroos in Amman in 2015 and Syria provided a challenge in the penultimate stage of World Cup qualification, all three teams are likely to play reactively against a superior Australian team.

But if Arnold’s team progress, they may come up against the likes of Japan, Iran or South Korea – all of whom demonstrated their quality in Russia.

Arnold must fashion a system capable of adapting to all-comers in January, with limited time and a lack of playing opportunities.

That is a tall ask.

Who scores goals?

The million-dollar question.

Australia has not scored from open play in competitive international football since Tim Cahill’s strike against Syria in Sydney.

Aside from two Jedinak penalties, they went scoreless in 270 minutes of action in Russia.

Andrew Nabbout’s shoulder injury means the striker will be touch-and-go to make the Asian Cup squad.

His replacement for the Peru encounter, Tomi Juric has consistently underwhelmed in national team colours.

During the tournament van Marwijk lamented the Socceroos’ scoring difficulties.

“It is hard to train,” he mused. “It is a real individual special quality. That’s the last step.”

Unfortunately for Arnold, his Dutch predecessor failed to solve the riddle.

Jamie Maclaren provides one possible solution.

Despite a strong season at club level, Maclaren saw not a single minute of action in Russia.

Or does Arnold blood one or more of the younger, untested Australian attackers – a smattering of whom can be found in the A-League and across Europe.

If Australia is to have any hope of defending its Asian Cup title in January, an answer to the team’s goal scoring concerns must be found.

Plus ca change?

Finally, a bigger question looms over the Australian national team, which goes beyond the paygrade of Arnold.

There has been much introspection in the days following the Socceroos’ group stage exit from Russia.

Most raise issues rising well-above the immediate national team, instead concerned with structural problems at the heart of Football Federation Australia (FFA) and the domestic game.

There has been much hyperbole, as is inevitable in the heat of the World Cup.

But many criticisms are only too valid.

The ball is now with FFA.

If change is not forthcoming, Australia will likely find itself in an identical position in four years’ time, regardless of how the Socceroos perform in January.