Manchester United were hammered 4-1 by Como in the Champions League on Wednesday as the pressure increased on beleaguered manager Michael Carrick, while a late Declan Rice equaliser earned Arsenal a 2-2 draw away to Bayern Munich.
Elsewhere, Real Madrid thumped RB Leipzig 4-1 and there were also notable victories for Inter Milan, Aston Villa and Real Betis.
The most remarkable scoreline, though, came in driving rain on the banks of Lake Como, where United suffered their joint-heaviest loss in the Champions League in the last 30 years.
Deep Dive
How did Arsenal earn a 2-2 draw against Bayern Munich?
Why is Manchester United manager Michael Carrick under pressure after the Como defeat?
Where was the Bayern Munich vs Arsenal Champions League match played?
Nico Paz scored twice for Cesc Fabregas's Como, with Tasos Douvikas and Jacobo Ramon getting their other goals. This was a second 4-1 home win in this season's competition for the tournament debutants.
Joshua Zirkzee pulled one back at the death for United, but they are now seven games without a win in all competitions.
The Red Devils have just one win in the Premier League this season and have now suffered back-to-back losses in Europe. Carrick's position risks becoming untenable.
"I have not given my own position any thought," Carrick said.
{{/usCountry}}"I have not given my own position any thought," Carrick said.
{{/usCountry}}"For us to play in that way, it's not acceptable. It wasn't a good performance at all," he admitted.
Last season's beaten finalists Arsenal have seven points from a possible nine after Rice struck in the 82nd minute to earn a draw in Munich.
Bukayo Saka went off injured early on but his replacement Eberechi Eze fired Arsenal into the lead, only for Alphonso Davies to level before the interval.
Harry Kane set up that goal with a magnificent pass and then gave Bayern the lead from a second-half penalty, his 10th strike this season in all competitions.
But Arsenal hit back as Bayern registered a second straight Champions League stalemate.
"We looked dangerous, we got the goal and we had a moment there where we could have killed off the game," Kane told broadcaster DAZN.
“Probably a draw was a fair result overall... There's a lot of games and we've got players with injuries, players missing tonight, so we take the point and move on.”
- Real three from three -
Jose Mourinho's Real are one of five teams with three wins from three in this season's Champions League, as goals either side of half-time from Bernardo Silva and Arda Guler set them on their way at the Bernabeu.
Kylian Mbappe made it 12 goals in 12 games this season for Real before Tidiam Gomis pulled one back, but Yan Diomande completed Real's victory with a spectacular volley against his former club.
"We know every point is important to get into the top eight, we know we have to win as many games as possible -- we've won three and there are five to go," Mbappe told Movistar.
Villa also have a perfect record after three games, as they won 3-1 at home to Viking Stavanger with Ross Barkley's opener being followed by Emiliano Buendia's penalty and Henrik Heggheim's own goal.
Peter Christiansen got one back for the Norwegian champions who are still looking for their first win.
Inter had Alessandro Bastoni sent off midway through the second half before Carlos Augusto's late goal secured a 1-0 win at home to Shakhtar Donetsk, as the Italian champions got their first points.
Betis have maximum points as an Isco penalty handed them a 1-0 win over Feyenoord in Seville.
- PSG blow -
Club Brugge defeated Lens 3-0 in Belgium as Hans Vanaken, Joaquin Seys and Carlos Forbs all found the net.
Victor Osimhen sealed a 4-2 victory for Galatasaray away to his old side Lille in France, after earlier efforts from Yunus Akgun and Aleksey Batrakov and a Nabil Bentaleb own goal.
Teenager Soriba Diaoune got both goals for Lille, who have lost three out of three.
LASK of Austria have their first points after a fine 3-2 victory over Sporting in Lisbon.
Luis Suarez scored twice for Sporting, including an early penalty, but Christoph Lang, Sasa Kalajdzic and Krystof Danek all netted in between for the visitors.
Reigning champions PSG are top of the 36-team standings after beating Barcelona 4-2 on Tuesday, but the French side confirmed Wednesday that star winger Khvicha Kvaratskhelia ruptured the anterior cruciate ligament in his right knee in that game.
He will undergo surgery in the coming days amid doubts as to whether he will play again this season.