FC Barcelona visited Germany to take on Borussia Monchengladbach and successfully defeated the home side 2-1 to remain at the top of the group table. Gladbach took the lead first but Arda Turan equalised for the visitors. Gerard Pique scored the winning goal.
Arsenal beat Swiss champions, FC Basel 2-0 to retain their second position in the group table behind PSG. Theo Walcott scored a brace to ensure Arsenal's victory.
Manchester City's 10-match winning streak this season under new manager Pep Guardiola came to an end last night when they were held to an exciting 3-3 draw by Brendan Rodgers' Celtic.
Here are all the results from Day 2 of Game week 2
Ludogrets 1-3 PSG
Celtic 3-3 Manchester City
Napoli 4-2 Benfica
FC Rostov 2-2 PSV Eindhoven
Arsenal 2-0 FC Basel
Besiktas 1-1 Dynamo Kiev
Atletico Madrid 1-0 Bayern Munich
Borussia Monchengladbach 1-2 FC Barcelona