Erik Ten Hag says Manchester United must learn from Galatasaray draw in Champions League
and live on Freeview channel 276
Having lost three of four Group A games, Thursday’s key clash in Istanbul began in dream fashion as Alejandro Garnacho's early effort was followed up by a Bruno Fernandes rocket.
Hakim Ziyech pulled one back from a free-kick that Onana will be disappointed to have been beaten by and he was guilty of an even worse error after Scott McTominay scored United's third.
The summer signing somehow failed to deal with another Ziyech free-kick and substitute Kerem Akturkoglu soon lasered past him as a mad match ended 3-3.
The result leaves United bottom of their pool heading into the final round of fixtures, with the concession of 14 goals in just five Group A games the key issue.
"We scored also quickly after each other," United manager Ten Hag said.
"It's about the point when you are leading, when you are 2-0 up and you have to manage the game. Not so easy.
"We give free-kicks away and we have to defend them better twice. I have to say also that is Hakim. He is brilliant, I know that. He is extraordinary.
"To give free-kicks, it's difficult to defend as well. In such areas, we have to be in more control. It is always about incidents, always about details and some incidents we can manage better.
"As a team, we have to learn from it because we are conceding too many goals and it is unnecessary and avoidable. I am sure our team is experienced enough and capable enough to manage this and we will do better.
"What is enjoyable is the progress we have and the way we play football. We dictated the game, we scored so many goals - it was about plan, creativity, being proactive and brave. That makes me happy."
United should have scored more but Onana will be under the spotlight after this draw, having also been guilty of errors in the losses away to Bayern Munich and at home to Galatasaray.
While his key stoppage-time penalty save secured a win against Copenhagen, he endured another difficult Champions League night.
"I think as a team we played very well," Ten Hag said when asked about Onana. "We win and lose together. You see the progress in this team.
"It was enjoyable to watch that proactive, dynamic, brave and we scored great goals. Even after we had some setbacks, we kept going until the end and we should have won with big chances from Scott McTominay and (Facundo) Pellistri.
"Of course, I am disappointed because we should have managed the game better, we will learn from that.”
United are now sweating on their place in Europe, let alone the Champions League, heading into their group finale against already-qualified Bayern at Old Trafford.
"It would be more frustrating if we play poor," Ten Hag said.
"But the performance is very good, it is enjoyable to watch how we dictate the game, how we create chances, that is actually fantastic.”