Enzo Maresca made 10 changes to the side which beat Leicester in the Premier League at the weekend.

But the Blues dominated the first half, with Heidenheim goalkeeper Kevin Mueller keeping them at bay with a string of fine saves.

Chelsea needed only six minutes after the restart to break the deadlock, though, as Christopher Nkunku took a brilliant touch to control Jadon Sancho's cross before firing into the top corner.

Nkunku, behind Nicolas Jackson in Maresca's Premier League pecking order, has scored five goals in four Conference League games this season.

The German side improved after falling behind, though, and almost equalised in the 69th minute when Chelsea goalkeeper Filip Jorgensen produced a wonderful double save to deny Paul Wanner and Leo Scienza.

The two-time European champions killed the game off with four minutes left as Sancho notched his second assist of the match, teeing up Mykhailo Mudryk to drive a shot into the roof of the net after playing a one-two with Kiernan Dewsbury-Hall.