Mauro Icardi redeemed himself after missing a penalty
Mauro Icardi redeemed himself after missing a penalty by scoring the winner for Galatasaray at Old Trafford AFP

Manchester United crashed to a second successive Champions League defeat on Tuesday, losing 3-2 at home to Galatasaray, while Lens stunned Arsenal and Jude Bellingham once again inspired Real Madrid.

Mauro Icardi made amends for a missed penalty by scoring the winner for Galatasaray as the Turkish club twice came from behind at Old Trafford to pile more misery onto a deeply troubled United side.

United have lost their first two games of a Champions League group for the first time, leaving Erik ten Hag's men in danger of an early exit.

"The mental errors we make, you cannot allow them at this level. You get punished. This is difficult to control," Ten Hag told TNT Sports.

"We are all in this together. We were twice up and in control of the game. We expect more together."

Rasmus Hojlund was one of the rare bright spots for United, scoring two well-taken goals, but Galatasaray responded both times as Wilfried Zaha netted against his old side before Kerem Akturkoglu struck.

Icardi dragged a penalty wide after Casemiro was sent off for a desperate lunge following a dreadful ball out from goalkeeper Andre Onana, but the Argentine had the last laugh when he chipped home on 81 minutes.

United are bottom of Group A, six points adrift of Bayern Munich who came from behind to beat FC Copenhagen 2-1 in Denmark.

Lukas Lerager fired the Danes ahead early in the second half, but Jamal Musiala bagged a superb individual goal to haul Bayern level before teenage substitute Mathys Tel lashed in a fine strike late on.

Arsenal slumped to a first defeat of the season as Lens hit back to win 2-1 in northern France.

Gabriel Jesus gave Mikel Arteta's side an ideal start when he opened the scoring in the 14th minute to silence a raucous Stade Bollaert.

Adrien Thomasson soon brought last season's Ligue 1 runners-up level and the visitors saw Bukayo Saka limp off before half-time.

Wahi, the 20-year-old striker who became Lens' club-record signing when he joined at the start of the campaign, then fired home in the 69th minute and his side held on for a famous victory.

"It was a big night for us. We weren't able to take the result we wanted but we were able to learn," said Arteta.

Lens climbed to the top of Group B on four points, one above Arsenal.

PSV Eindhoven snatched a 2-2 draw at home against Sevilla in the other game in the group courtesy of Jordan Teze's stoppage-time equaliser after a late flurry of goals in the Netherlands.

England star Bellingham continued his sensational start to his Madrid career with a goal and an assist as Carlo Ancelotti's side beat Napoli 3-2 in Group C.

"What's so amazing about Bellingham is that he's only 20. He has great quality, a strong personality and character," Ancelotti told Sky Sport.

"He's a young man of 20 who's showing everyone what extraordinary talent he has."

Leo Ostigard headed Napoli in front but Bellingham set up Vinicius Junior to level before the England midfielder's brilliant run and finish put the Spaniards on top.

Piotr Zielinski converted a penalty to level for Napoli at the start of the second half but an unfortunate own goal from home goalkeeper Alex Meret handed Madrid victory.

Federico Valverde's thunderous drive from distance crashed back off the bar and hit Meret before bouncing back into the goal.

Braga ruined Union Berlin's home debut in the competition as Andre Castro struck a stoppage-time winner in a 3-2 victory.

Union were two goals ahead after Sheraldo Becker's brace but Sikou Niakate pulled one back before Bruma curled in a brilliant equaliser from 25 metres.

Castro broke Union hearts with a low strike from outside the area to give Braga their first points in their first Champions League appearance since 2012.

Marcus Thuram struck the only goal as Inter Milan won 1-0 at home to Benfica in Group D. Inter are level on four points with Real Sociedad, who beat Salzburg 2-0 earlier in the day in Austria.