Graham Arnold praised Australia's mentality after the Socceroos made a winning start to their World Cup qualifying campaign.

Mathew Leckie scored twice to lead Australia to a 3-0 win away against Kuwait on the road to the 2022 World Cup in Qatar.

Australia – who have qualified for the past four World Cups having reached the group stage in 2018 – opened the scoring in the seventh minute and did not look back thanks to Leckie and Aaron Mooy.

Also drawn in Group B alongside Jordan, Nepal and Chinese Taipei in the second round of AFC qualifying, Socceroos head coach Arnold was pleased with the result in tough conditions.

"I thought the first half was excellent. We came out with all intention to be on the front foot. We pressed them very well, we worked them really well, we didn't let them really have any chances, and obviously second half it was a bit less," said Arnold.

"The mentality of the boys was fantastic, but in these conditions you could see the fatigue kick in and I thought the three subs that came on made a big difference.

"The energy that the young boys have brought into camp has been great. We had a number of inexperienced players out there that are gaining great experience here in the Middle East and it is a great start to the campaign."

Hertha Berlin's Leckie captained Australia in the absence of injured skipper Mark Milligan in Kuwait City.

Leckie scored a first-half brace before Brighton and Hove Albion midfielder Mooy sealed three points seven minutes prior to the break.

"It is always tough qualification in Asia, especially away games," Leckie said. "We had a good training camp [and] we were fortunate that we only had one game this camp, so we had a good week to prepare.

"The boys showed a good mentality today, a lot of concentration, those are the things you need playing in these conditions. It is very warm, so I think it comes down to the mental game, 3-0 away, it is never easy, but we got the job done."