Record 15-time Champions League winners Real Madrid have been given a daunting draw for this season's competition after being handed matchups against Premier League giants Liverpool and Manchester City on Thursday.
Defending champions Paris Saint-Germain also face a tough journey to reach the knockout phase with matchups against the champions of Spain, Barcelona, and German champions Bayern Munich.
Madrid will visit English champions Liverpool in what could be a first return to Anfield for Trent Alexander-Arnold, who joined the Spanish giants this summer after 20 years at his boyhood club.
"That is, I am sure, a fixture that the whole world will be looking at," Liverpool coach Arne Slot said about another Madrid challenge.
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Madrid, who got two English opponents from the pot of highest-ranked teams, lost 2-0 at Anfield in the league phase last year. Xabi Alonso's side will host 2023 winners Man City, whom they beat in the knockout playoffs last season.
Madrid also will face Juventus in a repeat of their 2017 final win, and two Ligue 1 opponents, Marseille and Monaco -- where superstar forward Kylian Mbappé started his career.
If that wasn't enough, they also face a 4,000-mile journey to Kazakhstan's Kairat Almaty.
PSG, meanwhile, failed to draw any opponent from the lower-ranked nations. After drawing Barcelona and Bayern from the pot of top-ranked teams, Tottenham Hotspur came from the pot of third-seeded teams in a repeat of their tight Super Cup game two weeks ago. And the French champions were paired with arguably the two toughest opponents from the lowest-ranked teams: Newcastle United and Bilbao's Athletic Club.
Bayer Leverkusen, Atalanta and Portuguese champion Sporting Lisbon complete the title holder's slate of eight games in the 36-team league phase.
"It's always difficult," said PSG president Nasser Al-Khelaïfi, whose team stumbled to 15th place in the single-standings league last season before surging to their first Champions League title. "We forgot last season, we think about this season."
Other high-profile league-phase fixtures drawn in Monaco on Thursday include two-time winners Chelsea hosting Barcelona, while Arsenal, who were semifinalists last year, will face the beaten finalists in May, Inter Milan.
As well as welcoming back Alexander-Arnold and Madrid, Liverpool face away trips to the vibrant stadiums of Inter Milan, Eintracht Frankfurt, Marseille and Galatasaray.
The draw offered another chance of a notable return, with Man City legend Kevin De Bruyne set to head back to the Etihad with his new club Napoli. City will also travel north of the Arctic Circle to face Bodo/Glimt of Norway.
This is the second season of the league phase format with 36 teams playing eight different opponents on a weighted schedule through January and ranked in a single-standings table.
The weighted schedule gave each team two opponents drawn from each of the four seeding pots. Teams were seeded based on their ranking over five seasons of results in UEFA competitions.
Four newcomers to the main stage of the Champions League are: Bodo/Glimt, Kairat Almaty, Russian-owned Pafos and Belgian champion Union Saint-Gilloise.
Games in Bodo and Almaty shape to be the longest-ever trips for visiting teams, and their home games in January among the coldest in competition history. Bodo plays on a heated artificial turf field.
The computerized draw gave each team two opponents drawn from each of the four seeding pots. Teams are seeded based on their ranking over five seasons of results in UEFA competitions.
Games start on Sept. 16 and the final league phase matchday is Jan. 28. On that Wednesday evening, all 36 teams play in 18 games kicking off at the same time.
The top eight teams in the final standings advance to the round of 16 in March. Joining them will be winners of eight knockout playoffs, featuring teams ranked ninth to 24th, scheduled in February. The bottom 12 teams are eliminated.
Information from The Associated Press was used in this report.