To see today's press conference...

At today's announcement of his squad for the Beijing Olympics, Arnold said it was difficult to leave out such players but felt it was the right decision for the squad.

"The selection policy was over 14 games. And over two years I've been working with them," he said.

"And on form over that time and over the friendly matches these [other] players deserve to be in the squad."

Arnold added that the pair's reaction to the somewhat surprising decision to leave them out as being "not good".

"It's a mature squad," he added. "Apart from Velaphi, Spiranovic and Troisi, most are the oldest 22-23 year-olds.

"Unfortunately for guys like Burns, Djite, Vidosic, Williams and those sorts of guys, they're only 20 so they're in between the Olympic age groups which made it pretty difficult for them."

Arnold added that the Olyroos ability to cope with the heat will be a major factor when playing the big guns of world football at the Olympics.

He said there was no point picking any player who could not adapt to the heat.

"What I've learnt from Asia is that players who can't play in the heat, can't play in the heat," he said.

The Australians kick off their Olympic campaign against Serbia followed by massive games against a star spangled Argentina and Ivory Coast, which is expected to feature Chelsea striker Didier Drogba.

He added: "Maturity goes along with quality as well as athleticism and tactical nous.

"I've picked a squad that is very fast, athletic, that has done extremely well."

To see today's press conference...