Manchester United boss Erik ten Hag declared victory over Barcelona their biggest win of the season.
The 2-1 triumph sees United progress in the Europa League 4-3 on aggregate.
Ten Hag said: "We've had some good wins, Liverpool and Arsenal but I think this over two legs - Barcelona are La Liga leaders - to beat them it's a big win.
"For a European Cup second leg I think it was flat on both sides, no chances. One team has to go in the lead, we had big chances with Bruno [Fernandes] at the start of the game.
"One part of our game plan is that we can bring Antony and [Alejandro] Garnacho and open the wide areas you can get speed and running in behind and dribbles. They are both so brave, they don't fear anyone, they just take players on and I think that gives a boost to the whole team."
On potential opponents in next round, he added: "Doesn't matter for me, I'm focused on Newcastle now. Doesn't matter who will come, we have to beat them all we know that. We'll respect every opponent but if we are well prepared and have strong belief we can do it."