Group A
Bayern Munich vs Manchester United 4-3
New signing Harry Kane scored his first goal for Bayern Munich in Champions League as the hosts beat Manchester United 4-3 at the Allianz Arena. Casemiro's brace and Rasmus Hojland's goal went in vain as Leroy Sane, Mathys Tel, Serge Gnabry alongside Kane found the net for the German club.
Galatasaray vs Copenhagen 2-2
2 quick goals in the second half by Sacha Boey and Tete helped Galatasaray restrict Copenhagen to a 2-2 draw. Mohd Elyounoussi and Diago Convales had scored for the Danish club earlier.
Group B
Arsenal vs PSV Eindhoven 4-0
The Gunners began this year's Champions League on a high note as the English club thrashed Dutch club PSV Eindhoven 4-0. While Bukayo Saka opened the scoring in the 8th minute, Leandro Trossard, Gabriel Jesus and Martin Odegaard also found the net as Arsenal won their 9th straight home game in UEFA competitions against Dutch opposition.
Sevilla vs Lens 1-1
Angelo Fulgini with his 24th-minute goal levelled Lucas Ocampos' 9th-minute goal as Lens played a 1-1 draw against Sevilla.
Group C
Real Madrid vs Union Berlin 1-0
Jude Bellingham scored a last-minute goal as the 14-time European champions registered a thrilling 1-0 win at the Santiago Bernabeu against the German club Union Berlin.
Braga vs Napoli 1-2
Sikou Niakate's own goal helped Napoli register a 2-1 win at Braga in their first Champions League game of the season after Bruma equalised Giovanni Di Lorenzo's first half goal.
Group D
Benfica vs Salzburg 0-2
Romo Simic scored with a successful penalty and Oscar Gloukh found the net as Salzburg handed Benfica a 0-2 defeat at home.
Real Sociedad vs Inter Milan 1-1
Lautaro Martinez's 87th-minute strike helped Inter Milan equalise Brais Mendez's 4th-minute goal to play a 1-1 draw at the Reale Arena.