Borussia Dortmund have completed the signing of Freiburg defender Matthias Ginter.
Ginter, 20, has signed a five-year contract after returning from the 2014 World Cup where he was part of the Germany squad which won the tournament.
"Matthias is an intelligent and versatile German talent who has always been of great interest to us," Dortmund's director of sport Michael Zorc said.
"We're proud that he made it clear to us so soon that he wanted to move to Borussia Dortmund. BVB play in three competitions, are very ambitious and have made a conscious decision to go into the season with four strong central defenders."
Dortmund were beset by injuries last season, losing their entire back four at one stage. Veteran Manuel Friedrich was drafted in as temporary cover, but Ginter is now a more permanent option to rival Mats Hummels and Sokratis Papastathopoulos for a berth in the centre of the back four, while Neven Subotic is also expected back from injury soon to provide further competition.
That is of no concern to Ginter, who says he is realising "a childhood dream" by joining Dortmund.
"I was always a BVB fan and now I am getting the chance to wear the shirt of my favourite club," Ginter said.
"I would like to take the next step of my development in Dortmund and I'm already looking forward to experiencing the atmosphere of the Signal Iduna Park and being able to be part of this wonderful team after my World Cup vacation.
"I have only seen and heard positive things about this club."