To see all the pictures from the Socceroos' Friday training session........

McDonald has already flown back to Britain after being overlooked in Verbeek's 28-man squad on Tuesday.

But while McDonald is "disappointed" to have missed out, he and his manager Sticca see no need for a verbal volley which might jeopardise his future international prospects.

"It's a very emotional game and if you say something in the heat of the moment you can burn your bridges for the future," Sticca told AAP.

He says results will be the key indicator as to whether Verbeek's decision was the right one.

"The results in South Africa will dictate whether it was a good decision or a bad one ... time will tell.

"If Australia loses all three games and doesn't score any goals, it's going to look like he (Verbeek) mucked up, but if they do score and go through it will look like a great decision," Sticca said.

"If you are chasing the game, say we're losing 1-0 to Serbia in the last game, who comes on for us?" Sicca said.

Although the Middlesbrough striker has failed to score in16 internationals for Australia, Sicca said the fact remained that McDonald has found the net against the world's best club sides.

"Scott hasn't scored goals for Australia in the systems they've used but he's scored goals for every club he's played for against AC Milan and Manchester United," he added.

"He's a proven goal scorer, whereas some of the others in the squad are not."