The Danish defender has been on loan at Gladbach since July 2015 and has established himself as one of the Bundesliga's top defenders—he won the club's player of the season award for 2015-16.
His form has seen him linked with the likes of Bayern, Barca and City, while Gladbach are eager to keep him past the end of his loan spell in 2017.
But Eberl believes Chelsea will resist any approaches for Christensen, 20, and he will return to Stamford Bridge in the summer, per Anthony Chapman in the Sun:
It will be a hard task but I am hopeful that we can [keep him].