For Paris Saint-Germain and Manchester City, the quest for a first Champions League title will have contrasting assignments in the group stage.
Tough for PSG after being paired in a group with a Real Madrid side chasing a record-extending 14th European crown.
Relatively straightforward for City, which was placed in a group without any former champions and includes newcomer Atlanta.
PSG and City have been among the biggest spending teams of the last decades thanks to investment by state-linked ownership from the Persian Gulf.
In Group A, PSG will also face Club Brugge and Galatasaray. In Group C, City will also take on Shakhtar Donetsk and Dinamo Zagreb while facing doubts about its Champions League participation next season as the Abu Dhabi-owned team is investigated for Financial Fair Play breaches.
Liverpool lifted the European Cup for a sixth time in June and starts the defence with an undemanding group with Napoli the toughest opponent. Salzburg and Genk also await in Group E.
One of the most eye-catching groups is F - Barcelona, who won the competition for the last time in 2015, were paired with former finalists Borussia Dortmund and Inter Milan, alongside Slavia Prague.
Bayern Munich, who have won the European Cup five times like Barcelona, is in Group B with beaten 2019 finalist Tottenham, Olympiakos and Red Star Belgrade.
Group D sees Juventus paired with Atletico Madrid in a swift reunion after their round-of-16 meeting last year when Cristiano Ronaldo's second-leg hat trick overturned a 2-0 deficit to send the Italian champions through. They will also face Bayer Leverkusen and Lokomotiv Moscow.
Ajax made an unexpected run to the semifinals last year, but had to go through qualifying to reach the group stage. The Dutch club was drawn with Chelsea, which qualified as Europa League champion, Valencia and Lille in Group H.
Group G seems the least appealing for global television audiences: Zenit St. Petersburg, Benfica, Lyon and Leipzig.
The final is at Istanbul's Atatürk Olympic Stadium on May 30.
Group A: Paris St-Germain, Real Madrid, Club Bruges, Galatasaray
Group B: Bayern Munich, Tottenham, Olympiakos, Red Star Belgrade
Group C: Manchester City, Shakhtar Donetsk, Dinamo Zagreb, Atalanta
Group D: Juventus, Atletico Madrid, Bayer Leverkusen, Lokomotiv Moscow
Group E: Liverpool, Napoli, Salzburg, Genk
Group F: Barcelona, Borussia Dortmund, Inter Milan, Slavia Prague
Group G: Zenit St Petersburg, Benfica, Lyon, RB Leipzig
Group H: Chelsea, Ajax, Valencia, Lille