Hamburg chief Frank Arnesen is returning to Chelsea for another signing.
Arnesen hopes to take Romelu Lukaku on-loan for next season.
The young Belgian has spent this season in the stands at Chelsea and admits he's keen to move away on-loan next term to pick up his development after a difficult 12 months.
Hamburg already have Chelsea teammate Jeffrey Bruma on-loan and signed permanently Michael Mancienne and Jacopo Sala in the summer.