Fresh off their impressive 7-0 thrashing of Philippines Under-16's on Thursday, the Joeys looked to solidify their all-important top two position in group A to secure progressing through to the semi-finals.
But Tony Vidmar's side were forced to overturn a 2-1 deficit and an exquisite long-range strike, with Singapore Under-16's Rezza Yacobian spectacularly netting from his own half in the shadows of half-time.
After a cagey opening, Australia Under-16's took the lead through the in-form Mirza Muratovic in the 31st minute.
Muratovic, who bagged a hat-trick in their last-up win, benefitted from some superb lead-up play, before side-footing into an empty net.
But Signapore Under-16's hit back via Yacobian, who caught Joeys goalkeeper Noah James napping.
And things got worse for Australia Under-16's after Mahler William gave Singapore a 2-1 lead in the 54th minute.
Staring down the barrel of their second loss of the campaign, the Joeys needed a response and fortunately it was swift.
First it was Lachlan Brook, who produced a wonder goal in the 57th minute, and just moments later - Tony Vidmar's side regained the lead, ultimately, straight from the ensuing kick-off through Jaidon Seldon.
But the Joeys weren't finished there, as they continued to surge forward, and in the 67th minute, Brook bagged his brace to make it 4-2.
Australia Under-16s rounded out their impressive second-half display just nine minutes later through Muratovic, who made it five goals in two games, and captain Mark Moric in the 89th minute.
The 6-2 result sees as the Joeys maintain second spot in the group after on their final group stage clash against Malaysia Under-16s on Monday night (AEST).
