Manchester City are set for a quick reunion with Kevin De Bruyne as the English side were handed a home fixture with the Belgian's new club Napoli to kick off their Champions League campaign.
City will welcome Italian champions Napoli to the Etihad Stadium on Thursday, September 18, as the first matchday of this season's league phase stretches over three days.
De Bruyne joined Napoli in June after a highly successful decade in Manchester, which included winning the Champions League with Pep Guardiola's side in 2023.
The draw for the 36-team league phase of the competition took place on Thursday, but European football's governing body Uefa only released the full fixture list on Saturday.
Club World Cup winners Chelsea start on Wednesday, September 17, with a meeting with Bayern Munich at the Allianz Arena, the stadium where they defeated the German side in the 2012 Champions League final.
Premier League champions Liverpool will begin their campaign at home to Atletico Madrid the same night, while Newcastle United will mark their return to Europe's elite club competition by welcoming Spanish champions Barcelona to St James' Park the following day.
Arsenal, semifinalists last season, will be on the road for their first fixture away to Athletic Bilbao on Tuesday, September 16.
Tottenham Hotspur, who qualified for the Champions League after beating Manchester United in last season's Europa League final in Bilbao, start with a home game against Villarreal.
Reigning champions Paris Saint-Germain begin with a home game against Atalanta in the French capital, with other notable opening fixtures including Juventus against Borussia Dortmund, Real Madrid at home to Marseille, and Ajax against last season's beaten finalists Inter Milan.
Opening Champions League fixtures (21:00 unless stated)
Tuesday, September 16
Athletic Bilbao (ESP) v Arsenal (ENG) (18:45)
PSV Eindhoven (NED) v Union Saint-Gilloise (BEL) (18:45)
Juventus (ITA) v Borussia Dortmund (GER)
Real Madrid (ESP) v Marseille (FRA)
Benfica (POR) v Qarabag (AZE)
Tottenham Hotspur (ENG) v Villarreal (ESP)
Wednesday, September 17
Olympiacos (GRE) v Pafos (CYP) (18:45)
Slavia Prague (CZE) v Bodo/Glimt (NOR) (18:45)
Ajax (NED) v Inter Milan (ITA)
Bayern Munich (GER) v Chelsea (ENG)
Liverpool (ENG) v Atletico Madrid (ESP)
Paris Saint-Germain (FRA) v Atalanta (ITA)
Thursday, September 18
Club Brugge (BEL) v Monaco (FRA) (18:45)
FC Copenhagen (DEN) v Bayer Leverkusen (GER) (18:45)
Eintracht Frankfurt (GER) v Galatasaray (TUR)
Manchester City (ENG) v Napoli (ITA)
Newcastle United (ENG) v Barcelona (ESP)
Sporting (POR) v Kairat Almaty (KAZ)