The rapid rise and slow motion descent of the now 26-year-old Championship stalwart is a mystery encased in a riddle.
It began in the last phase of Ange Postecoglou’s reign, and has continued under his successors Bert van Marwijk and now Graham Arnold.
Luongo’s current place in the scheme of things was laid bare as Australia breezed past Kuwait 3-0 on the first rung of the ladder to the Qatar 2022 FIFA World Cup, as he remained marooned on the bench.
Brighton’s Aaron Mooy, fellow Championship incumbent Jackson Irvine and Austria-based James Jeggo - making only his second start for his country - were Arnold’s preferred choices in the engine room.
And even when it came to making a change deep into the second half, AGF’s Mustafa Amini was deployed ahead of Luongo.
Quite how it has come to this for the brash talent who ignited as a swashbuckling, goal-scoring, goal-creating presence in a triumph on home soil in 2015 is difficult to fathom.
Certainly his club form over the past four years at Queens Park Rangers - where he made 140 league appearances before the off-season switch to Sheffield Wednesday - has been solid.
Yet there-in may lie a clue into finding an answer to Luongo’s current plight.
Having set the bar so high for his country during his explosive entry onto the scene under Postecoglou, Luongo was tethered to a more defensive role under a succession of coaches at QPR - with the notable exception of Ian Holloway.
Some of the lustre was instantly lost at club level as Luongo embraced a less glamorous side to his game.
And the fallout for his country appears to have cost him.
Ex-Socceroos attacking midfielder Brett Holman, who retired ahead of the 2014 World Cup with 63 caps, believes Luongo’s club dynamic hasn’t helped him with the green and gold, where the likes of Mooy, Tom Rogic, Mark Milligan, Jedinak and now Irvine, Jeggo and Amini were, or are, also in the mix.
“I think you have to look at his club football,” said Holman.
“In his earlier days at Swindon he was more of an attacking threat and that seemed to change at QPR where he seemed to be dropping deeper and deeper.
“He has a good leap on him and score in the air and on the ground but that seems to have gone out of his game, and that’s maybe down to the way his club managers have chosen to use him and what they saw in him.
“He’s fallen back a bit which is a bit of a shame considering how his career took off.
“It’s a positive and a negative for him because in one way he’s been too good to be left out at club level.
“But at the same time has played further back because his coaches may have preferred other options in an attacking sense.
“You never know - with national teams you have to be patient and sometimes out of nowhere you get rewarded and you have to take your chance when it comes again.”
Tellingly, Luongo’s nine goals for the Hoops all came in his first two seasons, whilst he’s managed six in 43 appearances for his country.
Yet he was still in pole position to start for Australia ahead of an underdone Jedinak at last year’s FIFA World Cup in Russia, starting in all the warm-up games before being dropped for the group opener against France.
Surprisingly, he didn’t end up being given a single minute in any of Australia’s three group games as van Marwijk instead pinned his faith in Jedinak.
Though bitterly disappointed, Luongo took it on the chin and with Arnold’s arrival a year ago hope of a resurrection sprung forth.
But a familiar pattern began to emerge at the AFC Asian Cup in the UAE in January, with Luongo making two starts and two appearances off the bench before crucially being left out of the 1-0 quarter final loss to the hosts.
“With Mass it’s a tough one - Arnie has different ideas and thoughts maybe and you can see that,” added Holman.
“There’s a lot of depth in that midfield area, you look at James Holland and he was probably unlucky to miss out on being picked.”
Luongo must now distill his displeasure into performances for the Owls, where he’s made four league appearances off the bench so far.
He was man of the match over 90 minutes in the 1-0 League Cup win at Rotherham and has it within himself to relight a green and gold flame that’s turned into a flicker.
