Leckie admits he must improve to reach World Cup heights

Matthew Leckie in action during the 2015 Asian Cup match between Oman and Australia (Getty)

Australia winger Mathew Leckie wants to eradicate the errors and tiredness from his game by the time the knockout stages of the AFC Asian Cup arrive, as he strives to make to reach the heights of his 2014 FIFA World Cup performances.

Leckie's penetrating play out wide was one of the highlights of the Socceroos' winless run in Brazil, where he established himself as an international class player.

By his own admission, he hasn't quite scaled those same heights in Australia's first two Asian Cup group games.

He showed glimpses of form in the 4-0 drubbing of Oman in Sydney on Tuesday, setting up a second half goal for substitute Tomi Juric with a glorious curling pass with the outside of his foot.

"There's a few things I'd like to do better, I guess," Leckie said.

"There's patches in the game where I'm a bit tired and I lack that attacking sort of mind."

The Germany-based 23 year-old acknowledged his World Cup form had raised expectations of what he might do in the Asian Cup.

"I had a pretty good tournament in Brazil, so the expectations were going to always be high coming into this tournament, to do well," Leckie said.

"There's times in the game where I'm very dangerous.

"There's times when I'm probably a bit tired and make a few errors, which hopefully in the next few games, especially in the knockout stages, I can polish that off and try to play out a great game."

While the Socceroos put four goals past both Kuwait and Oman, Leckie felt Saturday's group decider against Korea Republic in Brisbane would provide a more accurate barometer of their form.

"Korea is obviously going to be another step up," Leckie said.

"They are going to be solid, so I guess that will be the benchmark of really where we're at."

A draw would be sufficient for Australia to top the group, as it boasts a far superior goal difference to the Koreans, who have recorded two one-goal wins.