With the tie seemingly done and dusted after Lyon took a 4-2 extra-time lead, Manchester United pulled off the greatest of escapes to advance into the Europa League semi-finals.
It was an extraordinary battle at Old Trafford that saw the home side take a 2-0 lead before goals from Corentin Tolisso and Nicolas Tagliafico extended the game to extra-time.
Rayan Cherki added a third with a superb strike before Alexandre Lacazette seemingly put the game out of reach with a 109th minute penalty.
The Red Devils were handed a lifeline however when Bruno Fernandes converted his own spot kick, before Kobbie Mainoo waltzed into the box to level the tie.
With Lyon stunned, up stepped Harry Maguire to guide a header beyond a rooted Lucas Perri.
Suddenly, a stadium that has been starved of celebration for some time erupted into life.
Both supporters and players remained to soak in the atmosphere long after the final whistle having witnessed or played a part in the first major European football game to feature five extra-time goals.
"Moments like this make it all worth it", Manchester United boss Ruben Amorim said in his post-match press conference.
The Portuguese manager's struggles have been well documented since his appointment at Old Trafford but there will be hope that this is the type of performance that can help galvanise his side.
The 40-year-old added, "The sound in the stadium for Kobbie Mainoo and Harry Maguire's goals was the best sound I have ever heard.
"A lot of people want to keep shirts, I just want to keep that sound. It is the best sound in the world."
Athletic Bilbao await the Red Devils in the last four, with the first-leg away from home on May 1st before returning to Old Trafford a week later for the conclusion of the tie.