It was a victory that looked so unlikely at half-time as Barcelona led thanks to Robert Lewandowski's 18th-minute penalty after Bruno Fernandes' needless foul on Alejandro Balde.

But Antony's arrival for struggling forward Wout Weghost changed the course of the tie as it injected more pace into United's attacks, which the La Liga leaders failed to deal with.

Erik ten Hag's side now move on to Wembley, where they will look to collect their first silverware since 2017 when they face Newcastle in the EFL Cup final.

For Barcelona, it was the first time they have been eliminated from European competition without reaching the last 16 since 1998-1999, which is not quite what president Joan Laporta had in mind when he pulled all those economic levers last year.

It was also Barcelona's first defeat since October and ended an 18-match unbeaten run.

After the match, Ten Hag said: "It was a magnificent night. I think this is another step because when you can beat Barcelona - one of the best teams in this moment in Europe - your belief can be really strong because then I think you are able to beat anyone.

"I think we have great personalities... winning types.

"Everyone has a such a strong belief in this team and fight in this team and you can see it with the subs, they are bringing energy and quality and a different dynamic in games. All the subs, not only in this game, did brilliant."

Manchester United have scored six goals via substitutes in the Europa League this season, more than any other team

Fred the red menace

Fred has had plenty of detractors since his £47m move to United from Shakhtar Donetsk in 2018.

The chances are if Christian Eriksen had not been ruled out until the end of April through injury, he wouldn't even have started this game.

Yet, as Ten Hag has admitted, anyone capable of playing regularly for Brazil has to be a good player and this was one of those occasions when he proved it.

Fred scored for Manchester United after only two minutes of the second half

Fred's goal was an excellent effort as he moved into space on the edge of the area, unseen by Barca's Dutch midfielder Frenkie de Jong, who United spent so long trying to sign in the summer.

When De Jong did come across to pressure his opponent after Fernandes had played a superb through ball, he was too late to prevent Fred drilling home the equaliser.

The goal transformed the contest. Fred then used his energy to break down Barcelona counter attacks, make surging runs that unsettled the visitors and even did the simple passing right, which he quite often gets wrong.

Fred also followed up Alejandro Garnacho in having a shot blocked before a third effort from Antony brought their second goal and allowed United to join Arsenal in the last-16 draw.

Whoever they get, the first leg will be at home on 9 March.

Ten Hag's decisive half-time switch

Ten Hag has praised Weghorst for his industry but at this level - a Champions League game in all but name - he looked what he is, an emergency signing brought in at relatively little expense to plug a gap created by Cristiano Ronaldo's unscheduled exit before someone more suitable comes in next summer.

The continued injury absence of Anthony Martial means Weghorst is having to play a more prominent role than Ten Hag envisaged and it weakens his team overall.

Robert Lewandowski has scored 25 goals in all competitions for Barcelona this season

It was no surprise Antony replaced him at half-time, nor that the hosts' performance should improve so markedly as a result.

There were still some nervy moments, with De Gea producing a fine save to deny Jules Kounde after Jadon Sancho had failed to track the France defender and Raphael Varane booting Lewandowski's shot away from danger in injury time when it might have been rolling in.

But it was Ten Hag and his coaching staff celebrating at the final whistle.

The Dutchman has evidently transformed fortunes at a club that appeared to be going nowhere fast 12 months ago, although he knows it does need some silverware to really underline that they are on the right track.

United pay Motson tribute

United paid tribute to legendary BBC commentator John Motson.

The club placed a picture of Motson, who died on Thursday, on one of the tables in the area of the press box where the broadcast media sit, together with a candle in Motson's honour.