PSG beat Man City 4-2 with Guardiola watching as the Champions League sets a scoring record

Pep Guardiola came back to the Etihad Stadium as a fan. He watched his old team get taken apart in the first half.

Paris Saint-Germain, the two-time defending European champion, beat Manchester City 4-2 in the Champions League on Wednesday. It was City's first loss of the season.

A first-half blitz

Desire Doue cut inside and drilled a low shot from outside the box in the 13th minute. Less than two minutes later Ousmane Dembele headed in Doue's cross to make it 2-0. Vitinha added a third in the 32nd minute after a clever backheel from Warren Zaire-Emery.

City came out swinging after halftime. Erling Haaland scored in the 53rd minute but Maghnes Akliouche made it 4-1 with a long shot that goalkeeper Gianluigi Donnarumma could not keep out. Haaland scored again in the 75th minute. Donnarumma later saved a weak penalty from Ferran Torres. City finished with 27 shots.

It was City's first Champions League match since it was found guilty of breaking the Premier League's financial rules. Guardiola sat in the stands with club chairman Khaldoon Al Mubarak and chief executive Ferran Soriano. It was his first visit since leaving the club at the end of last season.

"These kind of teams, if you don't go toe-to-toe you struggle," City manager Enzo Maresca said. "We had to be more brave. Second half, we were."

Madrid storms back in Rome

Real Madrid trailed Roma 3-1 with less than 10 minutes left and won 4-3. Carlos Espi scored in the 83rd minute, Endrick headed in the equalizer two minutes later and Antonio Rudiger fired the winner in the 90th minute after Roma failed to clear a corner. Kylian Mbappe scored Madrid's first goal. Donyell Malen scored twice for Roma.

Goals everywhere

Liverpool won 6-3 at Austrian champion LASK as Bradley Barcola scored a hat trick and Ronald Araujo got his first goal for the club. Aston Villa routed Fenerbahce 6-0 for the biggest European win in club history, with Nicolas Jackson and Ross Barkley scoring twice each.

Teams scored 78 goals across Tuesday and Wednesday. That broke the record for a single matchday, which was 71. Six of Wednesday's nine games had at least five goals.

Elsewhere Bodo/Glimt beat Borussia Dortmund 1-0, Real Betis edged Porto 3-2 on a late Isco penalty and Stuttgart won 3-0 at Slovan Bratislava.