Dortmund sign Amini

The 18-year-old has been linked with a move to Europe for several months, with Celtic and Dortmund said to have been battling it out for the signature of the Central Coast Mariners player.

It was the Germans that prevailed, signing the teenager for an undisclosed fee reportedly worth 135,000 Australian dollars (€100,000 or £90,000).

Part of the contract stipulated that Amini is to remain with the Mariners on a 12-month loan deal, allowing him to represent Australia at the Under-20 World before returning to Australia to play in the 2011-12 A-League season.

"I'd like to thank Peter Turnbull and Graham Arnold at the Mariners for working on this with Dortmund," Amini said.

"I'm really excited to be joining Dortmund, they're a big club with amazing supporters.

"It would be amazing (to play for Dortmund) but first of all I want to have another great season with the Mariners, as well as a good Under-20 World Cup in Colombia."

The Mariners chairman Peter Turnbul expressed his joy at completing a deal which has proved to be beneficial for all parties.

"I am pleased we have been able to secure a much-improved deal for all parties, and thank Dortmund for their consideration of our requests," Turnbull said.

"We now have a deal that satisfies everyone. Musti's international future, the club's needs and more importantly, the fans.

"They will now be able to see Musti play out the balance of his original contract plus the Asian Champions League group stage."