Chelsea and Manchester United both recorded convincing wins on the opening night of the new Champions League season.
It was not to be such a good night for Celtic who were blown away by PSG while last season's beaten finalists Juventus also lost on Matchday 1, going down to the side they knocked out last season, Barcelona.
Playing in their first Champions League game for two years, Chelsea wasted no time reacquainting themselves with Europe's premier competition. Pedro fired them ahead against Qarabag, the champions of the Azerbaijan Premier League, before right back Davide Zappacosta marked his first start for the Blues in style with a goal.
César Azpilicueta and a first goal for Chelsea from Tiemoué Bakayoko ended the game as a contest before two goals from Michy Batshuayi completed a 6-0 win.
The other game in Group C ended in a 0-0 draw between Roma and Atletico Madrid.
Despite finishing 6th in the Premier League last season, Manchester United were given a route to the Champions League by winning the Europa League. They came through a tricky looking tie at home to Basel comfortably thanks to goals from Marouane Fellaini, Romelu Lukaku and Marcus Rashford.
It wasn't all good news for United, though, as Paul Pogba went off injured.
CSKA Moscow came from behind to record an impressive away win against Benfica with the winner coming from Timur Zhamaletdinov.
PSG are for many people the favourites to win the Champions League this season and they showed why with a superb attacking display against Celtic.
Neymar, Mbappe and Cavani were all on the scoresheet in a devastating first half spell. The Scottish champions were better in the second half, but an own goal and a second from Cavani would ultimately condemn Brendan Rodgers' side to their heaviest home defeat ever in Europe.
Bayern Munich got their campaign off to a winning start with a 3-0 win over Anderlecht. Robert Lewandowski gave them the lead with a penalty that also saw Sven Kums sent off for the Belgians. Second half goals from Thiago Alcántara and Joshua Kimmich broke the stubborn resistance of Anderlecht.
Before tonight, Lionel Messi had never scored past Juventus goalkeeper Gigi Buffon. He made up for it tonight with two goals as Barcelona beat last season's finalists 3-0 at the Nou Camp.
Messi scores his first ever goal against Buffon. And it's a beauty.— Gary Lineker (@GaryLineker) September 12, 2017
There was late drama in the other game in Group C as Sporting Lisbon nearly blew a 3-0 lead away at Olympiacos.
Two goals from Felipe Pardo had given the Greek side hope of completing a remarkable comeback but they would ultimately pay for conceding three goals in the first half.