Sunderland midfielder Dong-Won Ji, who earlier this week completed a loan move to Augsberg in the German Bundesliga for the rest of the season, will join Borussia Dortmund on afree transfer in the summer, the club confirmed on Friday. Ji scored five goals in 17 appearances for Augsburg during a loan spell in the second half of the 2012-13 campaign. The 22-year-old has alsoscored eight times in 26 appearances for South Korea.