The Melbourne-born 20-year-old winger has broken through with Eredivisie side Groningen in the second half of the season, and is firmly on the radar of Australia coach Ange Postecoglou and also Bosnia Herzegovina, the birthplace of his father.
With Postecoglou to name an extended 30-man squad on Monday for 'super' June, Hrustic would welcome a shock call-up that could conceivably see him involved against Saudi Arabia, Brazil and at the Confederations Cup.
"If it were to happen it would be an honour to represent Australia and be a part of that squad," said Hrustic, who has been closely watched by Postecoglou.
"I can't say if it's going to happen or not ... I will just have to wait and see just like everybody else."
But the former South Melbourne junior, who joined Schalke's youth system at 14 before heading to Holland three years ago, is not yet closing the door on Bosnia.
"I am still young and will wait and see what's best for my career," he added.
"I've spoken to my parents and agent about it, but at the end of the day it's my choice and I will pick what is best for me.
"There are all sorts of problems you can have in your life ... and this is one of the good ones to have."
Hrustic made his sixth appearance of the season - off the bench - in the 4-1 overnight loss to AZ Alkmaar, a defeat which has all but killed off Groningen's Europa League qualification hopes ahead of Sunday's second leg.
He has scored once, impressed with his pace, trickery and penetration, and been tipped by Australia defender and Groningen teammate Jason Davidson as a Socceroo in the making.
He will not be tied to either Bosnia or Australia until capped at senior level in a FIFA-mandated tournament.
Hrustic made a big impression on Australia under-23 coach Josep Gombau at a recent development camp in Spain and the race for his allegiance is hotting up with Bosnia under-21 coach Vinko Marinovic inviting him to join his squad in camp for matches next month.
Hrustic reiterated that Australia could be his first preference, by adding: "Look, I have something in the back of my mind, having grown up in Australia and having Ange as my coach (in an elite training program) at the age of 12."
But he is fully aware that Bosnia has some "big names" in their midst and he is in regular contact with Schalke defender and Bosnian international, Sead Kolasinic, who has been advising him on the next step.
To counterbalance that, Davidson, who returns to parent club Huddersfield at the end of the season, has also been giving him "some tips".
"Like I said, the decision I make will be what's best for me and my career," he reaffirmed.
Hrustic took a lot from his stint under Gombau.
"It was a great experience ... I was there three days and played a game against Austria," he said.
"I think I showed myself quite enough and I think that Josip Gombau was quite happy."
While his own international destiny is yet to be determined, Hrustic - who has inked a contract extension at Groningen - would love to see Davidson recalled to the Socceroos fold.
The left-back has been superseded by Brad Smith and Alex Gersbach but has put in a solid season in Holland.
"Jason's shown himself really well and he deserves to be playing at a top club," he added.
"I also feel he deserves to be called up again by the Socceroos next week.
"He's been playing really well and I wouldn't be surprised if Ange called him in again.
"We've became good friends on and off the field, and I am learning still from him.
"He has a lot of valuable experience."