Chelsea's 19-year-old Dutch defender Jeffrey Bruma has joined Hamburg on an initial one-year loan.
The Netherlands international also has an option for a further year.
Hamburg sporting director Frank Arnesen played a key role in the move, just a few weeks after taking up his new role having left a similar post at Chelsea.
Bruma, who is under contract at Chelsea until 2014, will link up with former Blues team-mates Michael Mancienne, Jacopo Sala and Gokhan Tore.
Bruma joined Chelsea's youth set-up from Feyenoord as a 15-year-old in 2007.
He made his first-team debut in late 2009 and has since made nine appearances for the club.
The teenager also spent three months on loan at Leicester last season, making 11 appearances for Sven-Goran Eriksson's side.
"Hamburg is the best option for me," Bruma told Hamburg's official website.
"Here, I can play at the highest level in Germany."