Neymar starred as Paris Saint-Germain sent out a statement of intent with an impressive 3-0 Champions League victory over Bayern Munich on Wednesday, while Michy Batshuayi grabbed an injury-time winner as Chelsea won 2-1 at Atletico Madrid.
It took PSG less than two minutes to break the deadlock in the Group B clash against Bayern, as world-record signing Neymar teed up fellow Brazilian Dani Alves to hammer home.
Bayern piled on the pressure but failed to take their chances, before Edinson Cavani finished a sweeping counter-attack with an exquisite strike into the top corner.
Unai Emery's men finished off their visitors in the 63rd minute when Neymar pounced after Kylian Mbappe had bamboozled the Bayern defence.
PSG now lead the five-time champions by three points in the race to finish top of Group B.
Atletico were handed the opener against English champions Chelsea when David Luiz needlessly gave away a penalty and Antoine Griezmann slotted past keeper Thibaut Courtois.
But the Wanda Metropolitano -- as well as the watching Diego Costa signed this week from Chelsea -- was silenced as former Real Madrid striker Alvaro Morata headed in an excellent Eden Hazard cross.
Antonio Conte's men deserved all three points and snatched the win in the fourth minute of added time as Belgian subsitute Batshuayi picked out the bottom corner.
Chelsea are now clear of Roma at the top of Group C by two points, after the Italians held on to beat Qarabag 2-1 in the early kick-off in Baku.
Kostas Manolas and Edin Dzeko put the visitors two goals to the good inside quarter of an hour, and although Pedro Henrique pulled one back for Qarabag, the home side couldn't find a maiden Champions League point.
United outclass CSKA
Three-time winners Manchester United brushed aside CSKA Moscow 4-1 to maintain their unbeaten record in the Russian capital, with Romelu Lukaku continuing his extraordinary start to life at the club with a brace.
The Belgian striker headed Jose Mourinho's visitors in front, before Anthony Martial made it two from the penalty spot.
Lukaku tapped in his 10th goal of the season before half-time and Henrikh Mkhitaryan scored the fourth before a late consolation from teenager Konstantin Kuchaev.
The other game in Group A saw Basel make it back-to-back defeats for 10-man Benfica, with a stunning 5-0 thrashing in Switzerland.
Michael Lang slotted into an empty net and Dimitri Oberlin finished off a breakaway to get Basel off to a brilliant start.
Ricky van Wolfswinkel's penalty ended the game as a contest and Andre Almeida was sent off for a horrendous tackle, with the 19-year-old Oberlin completing a brace.
Basel's biggest ever win in the Champions League was sealed by teenager Blas Riveros.
Last season's runners-up Juventus struggled for long periods at home to Olympiakos, but eventually saw off their stubborn visitors 2-0 as Gonzalo Higuain came off the bench to score.
A brave effort from Olympiakos was in vain as Mario Mandzukic bundled in a second.
Barcelona overcame a stuttering display to edge out Sporting 1-0 in the Portuguese capital.
Lionel Messi and Luis Suarez both wasted excellent chances in the opening 45 minutes, but Ernesto Valverde's side were fortunate to score a 49th-minute winner through Sebastian Coates' own goal.
Barca lead Juve and Sporting by three points at the top of Group D.
Celtic cruised past Anderlecht 3-0 in what looks to be a fight for third place behind PSG and Bayern in Group B.
Leigh Griffiths grabbed the first goal shortly before half-time in Brussels and the Glaswegians wrapped it up in the second period as Serigne Kara put through his own net and Scott Sinclair rifled home.