German side Augsburg have signed Sunderland striker Ji Dong-won for an undisclosed fee.
The forward, who signed from K-League outfit Chunnam Dragon in a £2m deal in June 2011, was out of contract on Wearside at the end of the season.
Ji Dong-won scored just two goals before joining Augsburg on a five-month loan last season, where he impressed with five goals in 17 games.
He returned to the Stadium of Light in the summer, but failed to make an impact under either Paolo Di Canio or his successor Gus Poyet, his last appearance coming in the FA Cup third-round win over Carlisle.
Augsburg are currently eighth in the Bundeliga with 24 points from 17 games, 20 points behind leaders Bayern.