Karim Adeyemi scored a hat-trick and Serhou Guirassy a brace as Borussia Dortmund stormed to the top of the Champions League standings with a 7-1 demolition of Celtic, while Manchester City, Inter Milan, Arsenal and Barcelona got first wins on Tuesday.
Last season's finalists Dortmund followed up on their opening 3-0 at Club Brugge, leading 5-1 at half-time against Glasgow opponents who were brought down to earth after starting with a 5-1 success over Slovan Bratislava.
Also on six points are French debutants Stade Brest with a 4-0 triumph at Red Bull Salzburg, and Bundesliga champions Bayer Leverkusen who condemned AC Milan to a second defeat with a 1-0 scoreline.
City rebounded from an opening 0-0 against Inter with a comfortable 4-0 at Slovan Bratislava, Arsenal beat Paris Saint-Germain 2-0, Barca routed Young Boys 5-0, and Inter thumped Red Star Belgrade 4-0.
VfB Stuttgart drew 1-1 with Sparta Prague and PSV Eindhoven v Sporting had the same scoreline.
Dortmund on fire
The game in Dortmund started lively with three goals in the opening 11 minutes. The hosts' early lead from Emre Can's penalty was cancelled out by Celtic's Daizen Maeda in the ninth minute, but Adeyemi restored the hosts' advantage.
Adeyemi fired into the roof of the net in the 29th and completed his hat-trick from long range shortly before half-time for 5-1, after Guirassy converted another penalty.
Adeyemi limped off injured early in the second half and Dortmund's intensity dropped a little but Guirassy in the 66th and Felix Nmacha in the 79th completed Dortmund's biggest win in the elite event.
"It was a special game for me, the first hat-trick. Today every shot went in," Adeyemi told Amazon Prime. Looking at his injury, he added: "The thigh, I hope that it isn't bad and that I can return quickly."
Leverkusen edge Milan
Leverkusen wasted a series of chances before finally finding the net in the 51st when Victor Boniface struck at the far post after Mike Maignon denied a first attempt from Jeremie Frimpong.
Having lost their opener 3-1 against Levirpool, seven-time winners Milan fought back and came close to an equalizer when Theo Hernandez' deflected shot hit the crossbar.
Brest 2, Austria 0
Brest had opened 2-1 over Sturm Graz and were also too strong for their next Austrian opponents Sazburg.
The French snatched a 24th lead from Abdallah Sima. Three goals within nine minutes midway through the second half ended the match as a contest, with Mahdi Camara on target in the 66th, Sima again in the 70th and substitute Mathias Pereira Lage in the 75th.
City coast in Bratislava
City were 1-0 up from Ilkay Gündogan's eighth-minute volley which took a big deflection to leave Bratislava goalkeeper Dominik Takac stranded. Phil Foden doubled the lead in the 15th into the bottom left corner.
The English champions hit the woodwork three times before Erling Haaland finally got on the scoresheet in the 58th after being released by Rico Lewis. Foden set up youngster James McAtee for his first goal in the competition in the 74th.
"I don't think it was easy. It was tough to break them down and we have to give them respect. We did the job," Foden told TNT Sport. "I had more chances to score and a few of the other lads did too. Delighted with 4-0 but we could've had a few more."
Inter also 4-0
Hakan Calhanoglu struck with a free-kick in off the left post in the 11th for an early Inter lead. Marko Arnautovic got the second in the 59th after Red Star lost the ball deep in their half, Lautaro Martinez came on the slot the third into the far corner in the 71st, and Mehdi Taremi converted a penalty for the final 4-0 score.
Barca hit five
Robert Lewadowski slotted into the empty net to give Barca an early lead, and captain Raphinha fired the second in the 34th from short range. Three minutes later Inigo Martinez headed home for 3-0.
Lewandowski headed the fourth from point-blank range and then wet off for Frenkie de Jong who had been sidelined with injury since April. The Swiss opponents' misery was completed by a Mohamed Ali Camara own goal.
Arsenal win as well
Germany striker Kai Havertz headed Arsenal ahead off Leandro Trossard's cross in the 20th minute, with PSG keeper Gianluigi Donnarumma not looking good.
The Italy international was beaten a second time by Bukayo Saka's free-kick from the wide right which went into the far corner through a crowded goalmouth.
The other matchday 2 games are Wednesday, including holders Real Madrid at Lille, Aston Villa v Bayern Munich and Liverpool v Bologna.
Source: www.dailyfinland.fi