Augsburg have signed South Korea international Koo Ja-Cheol from Mainz on a two-year contract.
Koo, now 26, scored eight goals in 36 games for Augsburg while on loan from Wolfsburg during the 2012-13 season and returns on a permanent basis.
"After he left Augsburg we remained in regular contact," director of sport Stefan Reuter told his club's official website.
"When this opportunity to sign him arose, we seized it.
"He knows the club, the surroundings, as well as the coach and the team, so Koo...