Manchester United's woeful season lurches from one damaging loss to another as Galatasaray took advantage of some calamitous defending to record a comeback Champions League 3-2 win at Old Trafford.
Ten-man United led twice through young striker Rasmus Hojlund, the second a brilliant effort as the 20-year-old took advantage of Davinson Sanchez's slip to race 50 yards and beat Fernando Muslera with a deft finish.
But the hosts could only hold their advantage for a combined 10 minutes, as first old-boy Wilfried Zaha, then Kerem Akturkoglu levelled.
Then, after Mauro Icardi had failed to convert the penalty that followed a terrible Andre Onana mistake that led to Casemiro's red card, the Argentine made amends when he sped clear of the hosts' defence nine minutes from time and found the finish.
It is the first time United have started a Champions League group-stage campaign with successive defeats, and piles the pressure on manager Erik 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 defeat by Crystal Palace, five of their past seven games and six out of 10 in all competitions since the start of the season.
Man United 2-3 Galatasaray
Lens 2-1 Arsenal
Napoli 2-3 Real Madrid
Union Berlin 2-3 Sporting Braga
RB Salzburg 0-2 Real Sociedad
FC Copenhagan 1-2 Bayern Munich
PSV 2-2 Sevilla
Inter 1-0 Benfica