Melbourne-born Hrustic, 20, was the big shock selection in Ange Postecoglou’s preliminary 30-player squad for the upcoming matches against Saudi Arabia and Brazil plus the Confederations Cup.

The attacking midfielder’s emergence in the national set-up has been sudden, having previously never been capped at Australia youth level.

Hrustic was never part of an A-League club having headed to Europe to join German club Schalke 04 in 2012, before joining Groningen in 2015 on a three-year deal.

He rose throught the ranks at Groningen late this season, debuting for the first team in April and making seven Eredivisie appearances off the bench and scoring against PEC Zwolle.

There has been talk that there had been an approach from Bosnia and Herzegovina, where his father was born, about playing for their under-age national team.

In light of this, Hrustic’s teammate and close friend Davidson acknowledged the youngster’s rise has been sudden but said he was a talent that Australian fans should be excited by.

“He’s a good young talent,” Davidson, who has 22 Socceroos caps, told FourFourTwo.

“He’s an attacking player, super player. He’s good one against one and an exciting young player.

“When I first arrived here he was with the second team. He started training with the first team around January.

“He’s a top kid as well. We get along on and off the pitch.”

Davidson, 25, this week left Groningen after the expiry of his loan spell from Huddersfield but provided some wise words to Hrustic.

“My advice to him is to keep working hard and make sure he can be consistent and bring that into the team next year and play week-in week-out,” Davidson said.

“Once he establishes himself, it’s to work hard and try to keep that level and push forward.

“I’m sure he can have a bright future if he keeps level headed.”

Hrustic’s goal against Zwolle in mid-April prompted a celebration between the two Aussies, showing off their own handshake.

“We’re good mates on and off the field, we’re always together outside the pitch and joking around,” Davidson said.

“We had a handshake, he said ‘if one of us scores we’d do it’.

“We’d been waiting a while. It was a simple handshake. It’s good for me to celebrate with him, I’m happy for him.”

Photo credit: FC Groningen