Manchester United midfielder Kobbie Mainoo came off the bench to score in their 5-4 win over Olympique Lyon, leaving the fans impressed. The Red Devils booked their place in the semi-finals of the UEFA Europa League with a 7-6 aggregate scoreline against the French side.Ruben Amorim's side survived a huge scare in front of their fans thanks to a rally in the closing stages of extra-time. They went down 4-2 before eventually claiming the 5-4 win, with academy graduate Mainoo scoring the equaliser in the 120th minute.With Rasmus Hojlund as the only fit senior striker in the squad, Amorim was forced to send on England international Mainoo to play up front after another disappointing display from the Dane. The young midfielder came on in the 86th minute and justified the decision of the coach to stick him up top with a goal at the death.Manchester United fans were very pleased with the display of the 19-year-old in his makeshift striker role, and some of them took to X to praise him. A fan praised him for being a "clutch" player and pointed out that he should be used similarly in the 2026 FIFA World Cup."Mainoo is such an incredibly clutch player. He’s gotta play last 20 of every world cup game next year", they wrote.Another fan hailed him as a star boy."My star boy. Thank the Lord for Kobbie Mainoo 😭😭😭", they posted.A fan praised the youngster, advising the club to not consider selling him."Mainoo is a hell of a baller, Manchester United shouldn’t sell", they wrote.Another fan praised him for the composure he showed with his finish."That finish from mainoo was something else under that pressure", they posted.A fan was full of praise for the young midfielder."Kobbie Mainoo, on earth and in heaven, you shall be famous❤️", they wrote.Mainoo showed great composure in the box to equalise for the Red Devils with all hopes seemingly lost. The teenager received the ball after a Casemiro flick-on before cutting back onto his right foot and bending the ball into the far corner. He has endured a disappointing few months at the club, with a loss of form and injuries costing him a regular starting berth.He scored with his only shot of the game and completed six of eight passes attempted during his time on the pitch. He had 13 touches of the ball in his 33 minutes of action and won both of the duels he contested.Manchester United book dramatic passage into Europa League semi-finalsManchester United kept their hopes of silverware alive after a dramatic 5-4 win over Olympique Lyon in their UEFA Europa League quarterfinal second leg. The Red Devils returned from the brink of despair to book their place in the last four of the competition.Following a 2-2 draw in the first leg, Manuel Ugarte gave Manchester United the lead at Old Trafford after ten minutes. On the stroke of halftime, Diogo Dalot doubled their advantage as they appeared to be coasting to the semi-finals.Lyon pulled one back through Corentin Tolisso after 71 minutes before Nicolas Tagliafico scored an equaliser for the Ligue 1 side seven minutes later. Tolisso received a red card in the 89th minute after a second booking, leaving his side a man down for extra time.Lyon scored twice in extra time through Rayan Cherki and Alexandre Lacazette to go 4-2 up with seven minutes remaining. Bruno Fernandes pulled one back from the spot, before Kobbie Mainoo and Harry Maguire scored to seal a brilliant comeback.Manchester United had just 41% of the ball on the night but created an xG of 3.20 and had eight shots on target. Their opponents, on the other hand, had an xG value of 2.44 from nine shots on target. They will now face Athletic Club for a place in the final of the competition.