Maruoka, who turns 18 on January 6, is expected to initially play for Dortmund's reserves in Germany's third division and Borussia have an option to buy him when the deal expires in June 2015.

The teenager follows in the footsteps of Kagawa, who signed for Dortmund from Osaka in 2010 for 350,000 euros (479,000 US dollars) before signing with Manchester United for 20 million euros last year.

Kagawa helped Dortmund win the 2011 and 2012 Bundesliga titles as well as the 2012 German Cup.