UEFA's new seeding system means Jose Mourinho faces the possibility of his Chelsea side being in the same group as his old team Real Madrid when the draw for the Champions League takes place in Monaco on Thursday.
The new system will see the pot of top seeds made up of the champions Barcelona and seven other domestic champions from the leading European leagues - including the Blues and Bayern Munich.
Real Madrid will be in pot two along with Arsenal, Manchester City and - pending their likely qualification - Manchester United. As English clubs cannot be drawn in the same group, it means there is more of a chance of Chelsea being drawn against Real.
So with the Champions League draw taking place tomorrow, we take a closer look at how it will work.
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When does the draw start?
At 4.45pm UK time in Monaco, though they may not get down to business right away. The ceremony includes the vote for, and presentation of, the 2014-15 UEFA Best Player in Europe Awards for men and women.
Remind us what the format is for the group stage?
The 32 teams will be drawn into eight groups of four, to play each other home and away between September and December. The top two teams from each group progress to the last 16 knock-out stages in February.
How will the draw be made?
The 32 teams will be split into four seeded pots with each group containing one from each pot.
Can teams from the same country be in the same pot?
Yes, they can.
Could Chelsea play Arsenal, or might there be another all-Premier League match?
Not at this stage, no. Teams from the same association cannot be put in the same group.
Is there anything new in the draw format this season?
Yes. A new seeding system means Pot 1 will be comprised of the holders and the champions of the top seven associations: Spain, England, Germany, Italy, Portugal, France and Russia. As Barcelona are also Spanish champions, the eighth-ranked Holland receive the vacant seeding place.
So which teams are in Pot 1?
Pot 1 will be made up of: Barcelona, Chelsea, Bayern Munich, Juventus, Benfica, Paris St Germain, Zenit St Petersburg and PSV Eindhoven.
What about the other pots?
The other pots will be finalised following the play-off results on Wednesday night. Real Madrid, Atletico Madrid, Porto, Arsenal and Manchester City are already guaranteed to be in Pot 2. Manchester United would also be in Pot 2 if they beat Club Brugge.
