Leckie a lock for Socceroos Cup selection

Mathew Leckie will be one of of 26 Socceroos pausing for celebration when Australia's World Cup squad is named on Tuesday.

Then, reality will hit.

"It's an amazing feeling," Leckie said of Cup selection.

"But at the same time ... we know how tough the games are that are going to be played."

Leckie is certain to be included when coach Graham Arnold announces his squad for the showpiece tournament in Qatar starting on November 20.

The 31-year-old, who will feature at his third World Cup, said emotions when selected were difficult to describe.

"We all work so hard," the Melbourne City midfielder said.

"The biggest key is like when you go to the national team, it's not easy to stay in the national team for a long period of time.

"For the players that do that, the majority of them are obviously people with very good mentality.

"And they have got that different mindset in the sense that they give everything every game and they know how important it is, because once you're out, it's hard to come back."

Leckie said World Cup selection could open doors worldwide for a batch of younger Socceroos.

"For so many different players in so many different age regions, it's a different opportunity for them," he said.

"It's the world stage - how many signings all over the world are made after the World Cup?

"That could be the start of a huge career for an Australian player.

"And for the more experienced ones, it's more trying to achieve something that has never been achieved."

Coach Arnold will release his 26-man squad at 1600 AEDT, with Australia's campaign starting against France on November 23 AEDT ahead of games against Tunisia and Denmark.

Goalkeeper Mat Ryan is also poised to attend his third World Cup.

Ryan was left out of FC Copenhagen's squad to face Lyngby on Monday morning (AEDT) with the club citing "knee problems" but there are no serious concerns and his withdrawal was only for precautionary reasons.