Gary Neville says Danny Welbeck is the man to provide Manchester United with the 'different edge' they need.
David Moyes' side secured their place in Friday's Champions League last-eight draw by turning around a two-goal first leg deficit to Olympiakos with a 3-0 win on Wednesday night.
Robin van Persie struck an impressive hat-trick in the comeback but, despite the Dutchman grabbing the headlines, Sky Sports expert Gary Neville believes Danny Welbeck was key to providing the right balance to the United team.
Neville said: "We said before the game that you need balance in a football team and it's not necessarily always the most talented players that make the best teams.
"You need someone that provides that different edge and Danny Welbeck provides that.
"In the first game, which was terrible at Olympiakos, he made the difference and he made the difference against West Brom.
"I was surprised that he didn't play on Sunday [against Liverpool] because you have to move defenders, you have to challenge behind them and there were two players on Sunday for United coming towards the ball and Liverpool just smothered them and suffocated them.
"What happened tonight was that those Olympiakos defenders thought to themselves, 'I'm running back towards my own goal.'
"Even in the quarter-final last year against Real Madrid he was United's best player at the Bernabeu, absolutely the best player.
"The whole way Antonio Valencia on the right and Welbeck on the left played enabled Robin van Persie to get more into the game, we saw more of those Van Persie type runs and also Ryan Giggs connecting with him.
"In games like this you need that energy and pace.
"It was better with Wayne Rooney deeper tonight as well, he provided a lot more support in midfield alongside Michael Carrick and Giggs, which meant there was probably more space for Van Persie to manoeuvre between the sides of Welbeck and Valencia."
Fellow Sky Sports pundit Jamie Carragher agreed with Neville's thoughts on creating a balance in the squad but questioned where Moyes' two big money signings, Juan Mata and Marouane Fellaini, will slot into the puzzle.
"You don't need every player on the pitch to be a 100m sprinter," said the former Liverpool and England defender.
"You need two or three in your team that can stretch your game and then you're creating space for your other players.
"I've been talking about pace in the Manchester United team and you look at this and you wonder where Mata comes into this team. He plays in a wide role, he's just spent £40million on him and he's got a lack of pace.
"With a performance like that Welbeck has to play because of the pace.
"It shows tonight, that Danny Welbeck is not the biggest name in the team or the squad but he has to play because of the pace. If that means Rooney, Van Persie or Mata has to miss out at times, it looks like he is as valuable."
It wasn't just Welbeck that put in a big performance for United on the night, 40-year-old Ryan Giggs defied the years to boss the game in the middle of the park and Neville says his leadership rubbed off on his team mates.
"They had someone in central midfield tonight who had the ability to pass the ball forward and, to be fair, they had runners," he said.
"He's a leader in a different type of way; the others look at him and gain composure from him - Michael Carrick looked more composed tonight - because he takes the ball in central midfield and plays the ball forward with his head up.
"To be fair United haven't played too many passes forward and haven't had too many runners and it enabled Robin van Persie to get into the match.
"I don't know why he hasn't been playing Giggs more. He hasn't played him now for about two months, usually Ryan Giggs would play every two or three weeks.
"He usually gets his games handpicked for him. Sir Alex Ferguson would say, 'right you're playing in two weeks' time'. That's not happened in the last few weeks. Maybe David Moyes has thought he needs to look at the younger ones for next season.
"Tonight he needed big performances and he got one from Ryan Giggs, he got one from David De Gea and he got one from Danny Welbeck. They were the three key players on the night."
What did you make of Manchester United's performance against Olympiakos? Should David Moyes be playing Danny Welbeck and Ryan Giggs more often? Have your say by commenting below.
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