BERLIN, Jul 4 (Xinhua) -- Werder Bremen have completed the transfer of defender Jan-Niklas Beste from league rivals Borussia Dortmund, the "Green-Whites" announced on Wednesday.

The 19-year-old left back will reinforce Bremen's defence for the upcoming season. Both Bundesliga clubs agreed to keep silence over further contract details.

"Jan-Niklas is a prospect player who can play on several positions on the left wing. He is currently recovering from a knee injury. After his rehab he will train with our first team," Bremen's sporting director Frank Baumann said.

Beste played his way through Dortmund's youth teams and provided three goals and six assist in 14 appearances for the Under-19 team. He made his first-team debut in the German Cup in August 2017.

"Werder Bremen is a well know club where I want to take my next career step," Jan-Niklas Beste told the club's official website.

The "Green-Whites" have finished the Bundesliga season 2017-2018 on the 11th position of the standings.