Mika Baur has given a first senior Germany call-up as new head coach Jurgen Klopp unveiled an unprecedented 44-man squad for upcoming Nations League matches and described the Celtic midfielder as an "exciting" prospect. The 22-year-old, who has already played for his country at youth level up to under-21s and joined the Scottish champions from Paderborn this summer, is one of 16 players to be handed their first call-ups by the former Liverpool manager. Teams are restricted to naming 20 outfield players and three goalkeepers for each match, but Klopp has split the group into two separate squads for their four upcoming fixtures.