Australia coach Holger Osieck has warned Asian Cup final opponent Japan that his defense is rock solid as the team looks forward to one of the biggest games in its history.

The Socceroos set up a showdown with the East Asian giant by emphatically hammering a shell-shocked Uzbekistan 6-0 in their semi-final on Tuesday evening, to give themselves a crack at some silverware for the first time ever.

The skilful and mobile Japan await them on Saturday at Al Khalifa Stadium after winning a nail-biting penalty shootout 3-0 against South Korea, in a game that finished 2-2 following extra-time.

The German-born Osieck knows Japanese soccer inside-out, having coached J-League stalwarts Urawa Reds to the AFC Champions League title in 2007, and he believes his side has the tactics to go all the way in Doha.

"The secret (against Uzbekistan) was the way we set ourselves up on the pitch. We were well structured, we had a great shape, we played high, we tried to create," he said.

"All the boys have done well and I'm very happy with the way our team has developed in the tournament. I'm full of praise and credit for them; what they did against Uzbekistan was fantastic."

While the scoreline pointed to their attacking prowess, Osieck focused on his defense, marshalled by captain Lucas Neill.

With veteran Fulham goalkeeper Mark Schwarzer between the posts, it has conceded just once in five games, against South Korea in the group stage.

"It's a result of our structure," said the 62-year-old.

"The entire team works well defensively. We are very compact and the defense starts with the strikers, they close the opponents down and we are very well-structured behind them.

"When the opposition dribble into midfield, they run into a wall. We win the ball and we play our game. It sounds simple but it took some time to get the structure together.

"The more we play together, the better we become."

They were far too good for the Uzbeks, who came into the game in impressive form but capitulated under the early pressure.

Galatasary forward Harry Kewell got the opener on five minutes, rifling a left-foot drive into the bottom right-hand corner after a neat exchange with Matt McKay.

Asian player of the year Sasa Ognenovski doubled its lead 11 minutes before halftime when he emphatically buried a shot from 12 yards out.

Blackpool's David Carney put the game beyond doubt on 65 minutes and when Uzbekistan striker Ulugbek Bakaev was sent off soon after, the match was effectively over.

Australia started running riot, with Blackburn Rovers' Brett Emerton getting a fourth, Carl Valeri a fifth and Robbie Kruse a sixth as the shell-shocked Central Asians went to pieces.

It was Australia's biggest victory since beating the Solomon Islands 7-0 in 2005 and the biggest win by any team at the Asian Cup since 2000.

Neill insisted the ease with which it dispatched Uzbekistan would not make it complacent against Japan, which has won the title three times.

"Players are going to have confidence now in front of goal ... and at the other end, we're one goal in five games now so we're going to be hard to break down too," he said.

"We can't ask for any more going into a final."