Bayern Munich suffered their first loss under coach Carlo Ancelotti, going down 1-0 at Atletico Madrid in the Champions League as Barcelona fought back to beat Borussia Moenchengladbach 2-1.
Yannick Carrasco notched the only goal for Atletico against Bayern in a repeat of last year's semi-final, won by the Spaniards.
Atletico, despite missing a late penalty through Antoinne Griezmann, now top Group D on six points while Bayern are second on three with Rostov and PSV Eindhoven each on one after a 2-2 draw in Russia.
Gladbach's Thorgan Hazard netted for Borussia in the first half before Arda Turan and Gerard Pique turned the game for Barcelona in Group C. Barca are top on six points with Manchester City, who drew a thriller 3-3 at Celtic, second on four.
In other matches Arsenal beat Basel 2-0, Paris Saint-Germain won 3-1 at Ludogorets Razgrad, Besiktas drew 1-1 with Dynamo Kiev and Napoli defeated Benfica 4-2.
Celtic gave everything in search of another famous European night in Glasgow but despite going in front three times through Moussa Dembele, an own goal from Raheem Sterling and Dembele again, City kept fighting back.
Fernandinho, Sterling and Nolito ensured Pep Guardiola maintained his unbeaten, if not winning, record in charge of City.
In Group A, Alexis Sanchez twice set up Theo Walcott for Arsenal to easily see off Basel. Arsenal share top spot with PSG who had a scare en route to winning in Bulgaria.
Natanael put Ludogorets, playing in Sofia rather than their home ground, in front but Blaise Matuidi equalized before the break. An Edinson Cavani double early in the second half, either side of a missed penalty from Cosmin Moti, settled the tie.
And in Group B Napoli won for a second time as a Dries Mertens double and goals from Marek Hamsik and Arkadiusz Milik led them over Benfica. The Portuguese got consolations through Goncalo Guedes and Eduardo Salvio.
Besiktas are second after another draw having led Kiev through a wonderful Ricardo Quaresma free kick. However, Viktor Tsigankov converted a set piece to earn the Ukrainians a first point.
