The Red Devils looked in complete control at 2-0 ahead through goals from Marcus Rashford and Rasmus Hojlund, and even when Pablo Sarabia got one back, Scott McTominay’s header reasserted dominance at 3-1.
However, Max Kilman kept the game alive before Pedro Netro seemingly secured a draw for Wolves by equalising in the 95th minute.
Then came Mainoo, who calmly curled the ball into the bottom corner seven minutes past the 90 to claim a big three points for his side.
The 18-year-old told TNT Sports of his first goal in the league after scoring against Newport County in the FA Cup on Sunday: ‘It’s a dream come true it’s such a tough place to come, they’ve had a good home run here. We had to get the win.
‘I’ve still not come down from it, I still feel like I’m dreaming to be honest.’
The teenager was making his eighth start in the league this season and he is quickly becoming a key part of Erik ten Hag’s side.
‘To start playing in the Premier League for my boyhood club is amazing,’ he said. ‘Now I’m just trying to get a good run of games in, win more games and get some momentum going.’
Manchester United captain Bruno Fernandes said of the midfielder: ‘He’s a big talent, I’ve said in the past, playing for the Under-18s two or three years ago and I said to a friend who wanted to see some Manchester United youth games, I said at the time the name of Kobbie. Without knowing he was going to be this player.’
Red Devils legend Rio Ferdinand added: ‘The composure that this kid shows at this level has been something that stands out immensely in his game.
‘He showed that in the youth team, he’s always looked a class player. To be able to transfer that composure and the way he plays straight into the first team and there’s no real change in that performance is the sign of somebody who’s got a real big future in the game.’
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