The 2021-22 Uefa Champions League group stage draw takes place on Thursday at 17:00 BST.
Here's what you need to know as reigning European champions Chelsea wait to discover their opponents:
What happened last year? Chelsea won the Champions League for the second time, as Kai Havertz scored the only goal against Premier League champions Manchester City in Porto.
What about this year? As European champions, Chelsea will be in pot one for the group stage draw. That means Thomas Tuchel's side will avoid the likes of German champions Bayern Munich, Italian champions Inter Milan and Spanish champions Atletico Madrid.
What's the worst-case scenario? Chelsea are in a favourable position in pot one, however, while clubs from the same country can also not face each other that still leaves Real Madrid, Barcelona, Juventus, Paris St-Germain and Borussia Dortmund as possible opponents from pot two. Elsewhere, AC Milan, Atalanta, Ajax and Porto could come from the other two pots.