Newly-appointed Sydney FC coach Graham Arnold has dropped a bombshell by declaring football giant Real Madrid has shown interest in Socceroos keeper Matt Ryan.

Speaking on ABC Grandstand's The Back Post program on Friday morning, Arnold was asked to give his view on the young crop of players likely to lead Australia's World Cup charge.

Arnold said Ryan, who he coached at the Central Coast Mariners and who currently plays in Belgium for Club Brugge, was in the sights of Real Madrid.

"Matty Ryan left here last year. He's gone across to Belgium and he's the best keeper in the league," Arnold said.

"I do believe and I have heard that he's getting interest from Real Madrid, he's been doing that well.

"That kid won't be fazed by anything."

While Arnold was full of praise for Ryan and the crop of young Socceroos likely to be thrown into the fire in Brazil, he also lamented the fact it had taken too long to clean out the "golden generation", a decision that had made coach Ange Postecoglou's task "more dificult".

"It's a pity, I was involved in 2010 and the turnover of players maybe should have happened earlier from the golden generation, but it didn't and it's put Ange in a more difficult position," Arnold said.

"But knowing Ange, he'll do a great job and the players will be ready.

"Ange has stated from day one that he'll never be scared to give those kids the opportunity. Do they have the quality? I believe they do.

"Ange is a guy who puts a lot of belief in the players. You can see the way they play football is that he always wants to give them opportunity to play.

"No matter what team goes out there, they'll do Australia proud."