The Red Devils legend turned pundit is confident that Jose Mourinho has managed to build a good unit during his 14 months at Old Trafford.
Plenty of money has been spent, including the £89m world-record purchase of Paul Pogba last summer.
Seven players have arrived under Mourinho’s stewardship and he has admitted he would like and eighth before the window closes on August 31.
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“One world class winger and it would be a complete squad”
He’s in the market for a winger with Ivan Perisic and Gareth Bale linked.
And if the Portuguese can get a wide man in, Neville thinks his old side will have a top squad.
He said: “Is Rashford a wide player – not really?
“That is where United could get one world class winger and it would be a complete squad.
“They have to challenge this year.
“Last season was not good enough and it was a big under performance from the players.”