It follows a year of progress for the 19-year-old defender after being elevated into Jose Mourinho’s first team squad last season. He made his debut in the Capital One Cup and followed it up with action in the FA Cup and Barclays Premier League.

Last month Christensen made his senior international debut with two substitute appearances for Denmark and played at the European Under-21 Championships, when his nation made the semi-finals. Since joining Chelsea in 2012 he has won the Under-21s Premier League, UEFA Youth League and FA Youth Cup.

Borussia Monchengladbach will play in the Champions League in the forthcoming season having finished third in the German top flight in 2014/15.