Beating Barcelona takes Man Utd's Ten Hag transformation to another level
Second half goals from Fred and Antony secured a memorable United win as the La Liga leaders were beaten 2-1 on the night and 4-3 on aggregate.
The fact that United's reward is merely a place in the last 16 of the Europa League shows there remains a long way to go for the three-time European champions to rediscover their past glories on the continental stage.
But momentum is building under the former Ajax boss with United still in the hunt for four trophies in Ten Hag's first season in charge.
A six-year wait for silverware could come to an end when United face Newcastle in the League Cup final on Sunday.
Without a league title in a decade, United are just five points adrift of Premier League leaders Arsenal and also into the FA Cup last 16, where they face West Ham at home.
For a long time since Alex Ferguson's departure in 2013, Old Trafford lost its aura as an intimidating destination for visiting sides.
But no one is looking forward to a trip to the Theatre of Dreams with United unbeaten in 18 games in all competitions at home.
'Strong belief'
Embarrassing defeats to Brighton and Brentford to begin Ten Hag's time in charge are now a distant memory.
Barcelona joined the list of big names beaten on home soil in recent months, joining Arsenal, Liverpool and Manchester City.
"You need a strategy to build it but also results to get that strong belief," said Ten Hag on how he has lifted United out of the mire of a miserable 2021/22 season when they finished sixth in the Premier League.
"That is another step because when you can beat Barcelona, your belief can be really strong because you are then able to beat anyone."
Buoyed not only by results on the pitch, but the potential departure of unpopular owners the Glazer family, the United fanbase is jubilant.
"The fans have been with us in the toughest moments," said United's captain for the night Bruno Fernandes.
"This season we have been really good because they are always behind us but this is something different.
"You can feel between them and us there is something special, Old Trafford was bouncing that is why we got the result."
Despite the Europa League's second tier status, this was almost certainly United's finest night in continental competition since eliminating Paris Saint-Germain from the Champions League last 16 in a dramatic night at the Parc des Princes four years ago.
The wait for such a European night under the lights at Old Trafford goes even further back to when Barcelona were beaten in the semi-finals of the 2008 Champions League.
"You can see what it means for the players. We haven't seen that for such a long time," said Paul Scholes, who scored the winner that night.
"To see the passion that these guys have for Manchester United is just fantastic, especially the reaction to the crowd."
Ten Hag is hoping this is just the start on United's road back to competing at the highest level in Europe.
"We have the potential to beat the big teams," he added. "We have beaten City, Arsenal, Liverpool. If we show discipline and team spirit this team can do a lot."