The £47.2million summer signing from Inter Milan was at fault for the opening goal in a thrilling group clash at the Allianz Arena, as he let a Leroy Sane strike squirm past him.
It wasn’t a great look for the Cameroonian, who has seen 14 shots end up in the back of his net in just six games, heaping the pressure on both him and his defence.
The Red Devils have conceded three or more goals in three consecutive games for the first time since 1978, and on this particular occasion, Onana felt solely responsible.
“It’s difficult,” the 27-year-old said. “It’s difficult to lose this way because I think in the beginning we started very good and after my mistake we lost control of the game.
“It’s a difficult situation for us, for me especially because I’m the one who let the team down. But the team were good, very good, but because of me we didn’t win the game.
“I am happy for the work of the team and we just have to move on. This is life of the goalkeeper and if we didn’t win today it’s because of me.”
Having requested to face the media to front up for his error, Onana went on: “I have to learn from it and be strong, move on.”
“It’s not an easy situation but I’m very happy for the comeback of the team. We were fighting until the end, but I have to recognise because of me we didn’t win.
“I have a lot to prove because, to be honest, my start in Manchester is not so good, not how I want.
“Play how I play today is one of my worst games and it’s difficult because we have big ambition, we are a very big club and we want to win everything.
“It was a big opportunity for us to bounce back after the situation we are facing. It’s tough, a tough time. We have to be together, we have to continue what we are doing, learn from our mistakes because it’s the only thing to do.”
It was a startling level of honesty from Onana, who received plaudits from Rio Ferdinand, who spoke of his ‘respect’ for the shot-stopper’s comments, and level of ‘character’ on display.
Nevertheless, over the 90 minutes it was hard to isolate just the first of the seven goals, with Diogo Dalot embarrassed by Jamal Musiala for the second, before a harsh handball decision gave Harry Kane the third from the spot.
In the dying minutes of the game it looked like it could have gone either way, but superstar sub Mathys Tel made sure it went Bayern’s, and he had plenty of help.
A switched-off Scott McTominay gave Joshua Kimmich all the time in the world to pick out a match-winning assist, and Dalot and Victor Lindelof could hardly have done a worse job at reading Tel’s run and finish.
So when Onana’s brutally honest comments were put to Ten Hag soon after the game, he was keen to bring a dose of realism to his troops
“It’s good he’s doing that but it’s about the team,” the Dutchman said. “Mistakes are being made but you have to bounce back as a team.
“If one player makes a mistake, it’s done, it’s gone. We have to believe as a team that we can always bounce back. Tonight we showed it.”
Next up for United is an eminently winnable trip to newly-promoted Burnley, where a fourth defeat on the bounce could be disastrous.
“Every game is important. Every game is huge,” Ten Hag commented. “We have to make our own luck. Nobody can help you.
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