Here's Simon Stone's report on Manchester United's defeat by Galatasary.
And Marissa Thomas' report on Arsenal's defeat by Lens on a bad night for the English teams in Europe.
You can check out the results on the other matches here, including Jude Bellingham's performance in Real Madrid's victory over Napoli.
Elsewhere, Burnley beat Luton Town 2-1 in the Premier League, while PGMOL has released the audio used by VAR during Liverpool's defeat by Tottenham.
It's another big night tomorrow as Newcastle United host Paris St-Germain. You can read the preview here.
Manchester City are also away at RB Leipzig. Preview here.
We'll see you tomorrow for more Champions League action.
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I am sure that in Fergie era the dressing room would have been anything but quiet ('It was very quiet in the dressing room' - Eriksen) after a performance like that.
One of them 'plastic' fans from London
Every week that goes by Man Utd and to an extent Arsenal are both showing us they are just not cut out for this level.
Alan
FT: Man Utd 2-3 Galatasaray
Simon Stone
BBC Sport at Old Trafford
Image source, Getty ImagesWhen he reflected on his unfulfilled United career on the eve of the game, Wilfried Zaha said he had emerged stronger for it.
There are some who argue he had the talent to operate at a higher level than Crystal Palace, and even now could be doing better for himself than the Turkish Super Lig.
Nevertheless, Galatasaray provide Zaha with the Champions League platform he craved, and almost a decade after making his United debut on this ground, he scored his first goal in the competition.
Unlike in September 2020, when he scored twice in a Palace win at Old Trafford but no fans were present to see it, this time Zaha was able to milk the celebrations, although they were nothing compared with those that followed the final whistle.
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Image source, Getty ImagesVarane said Man United could win the Champions League.
Robert
FT: Man Utd 2-3 Galatasaray
Simon Stone
BBC Sport at Old Trafford
Image source, Getty ImagesThis was a truly awful night for Erik ten Hag, who stood in the pouring rain before the final whistle hoping his side could snatch something to give them hope in a campaign that has been as bleak as the weather.
It is the first time Manchester United have started a Champions League group stage with successive defeats, and piles the pressure on Ten Hag, whose side are bottom of the table, four points behind their visitors who are second, behind Bayern Munich.
United have now lost two on the trot following Saturday's Premier League home defeat by Crystal Palace, five of their past seven games and six out of 10 in all competitions this season.
FT: Man Utd 2-3 Galatasaray
Manchester United
Image source, Getty ImagesRasmus Hojlund (20 years, 241 days) is the youngest player to score in his first two Champions League appearances since Erling Haaland in 2019 (19 years, 73 days).
Hojlund is the fourth player to have scored as many as three goals in his first two Champions League appearances for Manchester United, along with Dimitar Berbatov (4), Romelu Lukaku (3) and Wayne Rooney (3).
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Not even surprised by the Manchester United result, what’s the point of qualifying for the Champions League only to embarrass themselves?
Stev
FT: Man Utd 2-3 Galatasaray
Rio Ferdinand
Former England defender on TNT Sports
Image source, Getty ImagesYou have got to give Galatasaray credit, when the chances came they punished Manchester United. One minute we showed potential and something to be positive about. Then all of a sudden I had my head in my hands. There is not organisation in this team.
It is embarrassing. This is the Champions League, the lack of spatial awareness and lack of danger you are going to get punished and we saw that tonight.
FT: Lens 2-1 Arsenal
Image source, Getty ImagesLens goalscorer Elye Wahi has been named Uefa's Player of the Match.
He also assisted Adrien Thomasson's equaliser.
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Image source, Getty ImagesThree top players, Bellingham, Kane & Rice, were transferred in the Summer, but Man Utd trumped them all by g; Mount, Onana & Evans. Too late now, so start by benching Onana and resign De Gea. Did anyone notice Onana running back from the last minute corner. I'm 73 and would back myself against him in a 50m sprint.
Stuart
FT: Man Utd 2-3 Galatasaray
Manchester United
Image source, Getty ImagesManchester United boss Erik ten Hag, speaking to TNT Sports: "The mental errors we make, you cannot allow them at this level. You get punished. This is difficult to control. We are all in this together. We were twice up and in control of the game. We expect more together."
On Rasmus Hojlund's two goals: "Rasmus scored two great goals. We're happy with that but of course but we didn't win the game. He can be really happy with his goals."
On Marcus Rashford trying to square it to Bruno Fernandes instead of shooting: "That's up to Marcus. In such a moment he has to make a decision."
FT: Man Utd 2-3 Galatasaray
Paul Scholes
Former Manchester United midfielder on TNT Sports
Image source, Getty ImagesRasmus Hojlund took his two goals brilliantly.
There is a bit of Ruud van Nistelrooy in there. Mason Mount did well but he needs a goal. Sofyan Amrabat is not a left-back, he gets done for the third goal.
It was so wide open at the back. Victor Lindelof and Raphael Varane were soft and weak.
FT: Man Utd 2-3 Galatasaray
Manchester United
Rio Ferdinand to TNT Sports: "It's school football, it's Sunday football."
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Image source, Getty ImagesDavid De Gea was Manchester United player of the season consecutive years for a reason, it's now more than obvious that he was actually the one carrying the team, covered up for the team, none of Manchester United back four would start for any top team.
Papito
FT: Man Utd 2-3 Galatasaray
Pat Nevin
Former Scotland winger on BBC Radio 5 Live
Ignore Bayern Munich as they will go through, Galatasaray are not a great team, but they are a hard team to play at home.
Manchester United have no option - they have to beat Copenhagen home and away. They are outsiders now, but it is not impossible. You have got to go for every single game if you are Manchester United.
United are capable of going through, but I would not be betting on it the way they are playing at the moment.
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Conradk: No guts, no commitment, no Harry Maguire to blame. What's your excuse this time, Erik?
FT: Lens 2-1 Arsenal
Image source, Getty ImagesLens defender Kevin Danso speaking to TNT Sports: "We gave it our all today in front of our own fans.
"It was a difficult game. Arsenal had a lot of quality and made us sit back really deep, but we kept defending and kept our concentration. Luckily we won the game.
"The goal came from a mistake of our own, they didn't really create it, although it was a brilliant [finish] by Gabriel Jesus.
"We managed to get one back quickly and went on to win the game. It's a good result.
"At home we know how strong we are, in front of our fans. That's what we always try to do: win at home.
"I'm a bit gutted about the clean sheet, but we'll take the three points definitely."
FT: Man Utd 2-3 Galatasaray
Paul Scholes
Former Manchester United midfielder on TNT Sports
Disappointed. I don't think Manchester United played that badly, but all the talk before the game was a lack of goals in the team. We disregarded the defensive side of the game, It is not good enough they were all over the place.
FT: Man Utd 2-3 Galatasaray
Manchester United
Image source, Getty ImagesManchester United substitute Christian Eriksen, speaking to TNT Sports: "It's a big disappointment. It was very quiet in the dressing room. I think we had some good spells in game.
"No, I don't think it's about confidence. It's awareness and sharpness and wrong decisions at wrong times. A lot [needs to be done]. It's the details. If we don't make mistakes, we don't concede like we do.
"Luckily it's only the start of the competition and we know there are a lot of games to play."
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Max: Arteta needs to show he has a quality plan B, starting players like Smith-Rowe because he trusts them, not throwing him on at 70 minutes because he's desperate.
Louis: A typically mature and measured response to that game from many of my fellow Arsenal fans. Some of these people need a reality check.
Paul: Aw well. If you’re going to have an off night do it in a group stage where you have plenty of opportunity to recover. Not a disaster