The ex-Young Socceroo and Olyroo is one of four Australians now based in the Kingdom, and opened the season with two clean sheets and successive man-of-the-matches for east coast club Al Qadsiyah, instantly winning Duncan a new legion of fans.
Australia coach Graham Arnold will visit Saudi Arabia to check on the form of established squad keeper Brad Jones (Al Nasser), stopper Matt Jurman (Al Ittihad) and fringe candidate Rhys Williams (also Al Qadsiyah) in the build-up to October’s friendly against Kuwait.
January’s AFC Asian Cup in United Arab Emirates also looms beyond that.
Arnold is certain to also cast a speculative eye over ex-Newcastle Jets shot-stopper Duncan, who at 25 is determined to fast-track his claims for a spot in Australia’s senior set-up.
But the competition is fierce with Mat Ryan, Mitch Langerak, Danny Vukovic and Jones all ahead of him.
But Duncan - with the most saves made to date in the Saudi Professional League - is dreaming big.
As well as his Socceroos ambitions, he aims to use the Middle East as an eventual springboard back into Europe, where he had an abbreviated spell with Randers FC.
Speaking ahead of Thursday morning’s (AEST) clash against joint-table toppers Al Nasser - where comparisons with Jones can be drawn - Duncan said: “Playing for the senior national team has always been the number one goal of my career.
“I’ve been involved with the junior teams and a lot of my teammates from there, like Jamie Maclaren, Jackson Irvine and Mustafa Amini have all been involved with the Socceroos.
“They’re stepping up, or have stepped up, and that’s also my dream.
“If I perform well here, whether Arnie is coming over to watch games or not, then that gives me the best chance.”
After the disappointment of Denmark, Duncan feels he has “unfinished business” abroad and feels playing in a league which includes the likes of Al Nasser’s $30 million man, Nigeria star Ahmed Musa, shows he’s anywhere but a dead-end league.
“The budgets here are immense, the crowds can also be huge and there’s great ambition in the league,” added Duncan.
“Things have opened up from four to eight foreign spots, with seven players allowed to be on the pitch per club at any one time.
“Traditionally, they haven’t tended to bring in too many foreign keepers but that’s changed recently.
“I guess it’s up to Brad and I to prove that Aussie keepers are up there with some of the best in the world.”
Having signed a two-year deal, Duncan knows he has time on his side at both club and national team level.
“Brad and I are now playing in the same league, so we’re not only fighting it out against the same teams but we’re both hopefully pushing each other for a national team spot also,” he said.
“I also have ambitions to go back to Europe and do well. That’s the next box I want to tick.
“Hopefully playing in this league give me a chance to do that.”
