Bayer Leverkusen have completed the signing of Germany U19 defender Jonathan Tah from Bundesliga rivals Hamburg.
Bayern Munich will host Hamburg on the opening weekend when the 53rd Bundesliga season gets under way on August 14.
Bayer Leverkusen have completed the permanent signing of centre-back Kyriakos Papadopoulos from Schalke.
Borussia Dortmund have made their first signing after Jurgen Klopp's departure by landing midfielder Gonzalo Castro.
Liverpool give U21s more game time than Premier League rivals but top flight lags behind Europe.
Eintracht Frankfurt ended the season with a 2-1 win over Bayer Leverkusen.