Roman Burki joins Borussia Dortmund

Borussia Dortmund have completed the signing of goalkeeper Roman Burki from Freiburg.

The 24-year-old had joined Freiburg from Grasshoppers last summer, but he was unable to help the club to stay in the Bundesliga.

He has become the Dortmund's third signing of the summer, following the recent arrivals of Gonzalo Castro and Julian Weigl.

Burki has won two caps for Switzerland, but he was forced to withdraw from their most recent squad through injury.