Kewell struck the winner deep into extra-time, after the two sides went goalless after 90 minutes.

"I have always said Harry is one of the best players Australia still has," Osieck told Fox Sports after the game.

"I always had confidence in him. I'm very happy and now the sceptics will be more positive."

Osieck added the Socceroos once again had their chances to score plenty of goals, but was relieved to see his side eventually progress to a semi-final clash with Uzbekistan.

"I think in normal game time we definitely could have finished it off," he said. "We had a number of opportunities and they only had one.

"Then it became tight in over-time for some of my players, in particular the guys who were struggling with injuries, but they did very well and got through it."

Kewell admitted he was guilty of wasting a few chances, but said it was worth it to grab the winner.

"Again I had chances, should of put them away. But you're there all the time and the chance comes at the end and you put it away, so it's all worth it's while in the end," he said.

"We'd have liked to not have to go into the extra half an hour. But sometimes that's how football goes. Now we've got to enjoy this moment and relax, it's a job well done."

This Socceroos side makes history as the first Australian team to reach the Asian Cup semi-finals and Kewell was proud of the achievement.

"That was always playing on our minds," he said. "We always wanted to progress, we always wanted to take that step further and I think we done that tonight. We proved that to ourselves first and foremost. I'm proud of the boys, we worked hard and we deserve to be there."