The Swedish teenager had not only pulled United back into a tie that was in danger of slipping away, but he has also emerged as a thrilling prospect for the Premier League club who are struggling for long-term solutions in attack.
Marcus Rashford has had one of his worst seasons and was desperately poor against Atletico, while Cristiano Ronaldo’s goals and influence have started to wane.
Anthony Martial was shipped out on loan to Sevilla last month while Mason Greenwood is still suspended by the club after being arrested on suspicion of rape and assault of a woman. Jesse Lingard is set to leave for free in the summer.
So it was to great relief for supporters, players and coaching staff to see the 19-year-old Elanga step up to the plate and deliver on the biggest stage.
“I think he’s the future of our club,” said midfielder Nemanja Matic. “For a very young player to come here and score against Atletico Madrid, he will remember this moment forever. He deserved that.”
Interim coach Ralf Rangnick added: “It is a joy and fun to watch him play, I wish a few other players would take him as an example and as a role model.”
After seasoned Champions League specialists Ronaldo and Rashford had been starved for space by Atletico, Elanga seized the moment minutes after coming off the bench.
As United worked the ball forward, he escaped three defenders to scamper after a Bruno Fernandes pass and send an exquisite first-time finish into the net, scoring again three days after clinching a 4-2 victory at Leeds United.
The son of former Cameroon international Joseph Elanga, the winger was born in Sweden and joined United’s youth set up in 2014, being promoted to the first team at the end of last season.
For a player of such inexperience and youth, he oozes confidence.
“I told you how calm and cool I am and whenever I am given an opportunity,” Elanga told BT Sport with a cheeky smile, also keen to point out the decisive moment was his first touch in the game.
“I just do what I can do, I want to be the best player on the pitch and I appreciate the boss (Rangnick). He said to me to make the defenders scared and run in behind when I get the opportunity.”