"This was probably our most difficult match," said Australia coach Jan Versleijen. "Saudi Arabia knew what to do and we didn't have any solutions in the first half. We were lucky we didn't concede a goal."
"In the second half, we pushed on one of our midfielders to stretch them a little bit and from that moment, we got a little bit more control of the game and were more dangerous in the final third."
"We also knew if we could keep the ball for longer and keep the pace of the game fast, it would stretch them even more and you get more space. The moment we scored, we knew the game was almost finished."
The Dutchman also highlighted the contribution of Bulut, who has scored five goals in Zibo and plays for Czech club Mlada Boleslav.
"He always wants to go the shortest way to the goal and he's always a threat for any defence," he said. "He uses his physicality and his ability quite well and if there's something happening inside the box, Kerem is there and that's what he showed."
However, Bulut departed late on with an ankle injury, leaving Versleijen sweating on his fitness for the final.
"We'll wait for the medical report and then we'll see," he said. "If you play five games in 10 days, the players feel any knock more, so it will also be a challenge to get a team on the field for the final to compete for 90 minutes and maybe more."
Australia have an experienced squad. Kantarovski and Oar, who plays for the national team, competed in the 2008 AFC U-19 Championship, when the Young Socceroos beat DPR Korea 2-1 after extra-time in the quarter-finals.
Kantarovski and Oar also played in last year's FIFA U-20 World Cup with Gallagher, fellow defender Rhyan Grant and forward Kofi Danning, all key players in Zibo.
DPR Korea had already pulled off one upset by beating hosts China 2-0 in the quarter-finals and were underdogs going into a fascinating clash with Korea Republic, the tournament's most successful side with 11 titles.
However, Jong's header in first-half injury time and a 79th-minute goal by substitute Ri condemned Korea Republic to their third successive semi-final exit after winning the last of their titles in 2004. Yun Jong-su's side pulled off the win without star striker Pak Song-chol, who was suspended.
Australia, DPR Korea, Saudi Arabia and Korea Republic will all compete in next year's FIFA U-20 World Cup.