Arsenal winger Xavier Amaechi has completed a move to Hamburg after signing a four-year contract with the German second division club.
Hamburg will pay a fee in excess of 2.5m euros (£2.25m), plus several million in performance-related add-ons, while Arsenal have a sell-on clause but no buy-back option.
The 18-year-old England youth international, who passed a medical on Saturday before putting pen to paper, will wear the number 17 shirt at the Volksparkstadion.
Amaechi turned down a number of high-profile suitors and an offer to extend his Arsenal deal, which had a year remaining.
He received approaches from Barcelona, Bayern Munich, Inter Milan, Nice, Hertha Berlin and Championship sides, as well as late interest from four Premier League teams.