Manchester United defender Raphael Varane has credited manager Erik ten Hag for the confidence the players are now showing.
Varane says Ten Hag's system and tactics are making a difference.
He explained, "I think first of all it is the confidence. Secondly, it is discipline. Tactically we know exactly how we want to play, to manage the game.
"With a little bit more experience and the mentality of competition we have already improved a lot, and that is maybe the difference.
"I think on the last month we grow a lot. Tomorrow the atmosphere will be electric. We have to manage our emotions, be calm and believe.
"The next aim is to beat teams like Barcelona. It is a real challenge and a good opportunity."
Ahead of the second-leg of their Europa League playoff with Barcelona, Varane added: "For the second game we know exactly how we want to play - with patience, discipline and belief.
"I think we have a good team and are ready for that challenge."