Rio Ferdinand says the "landscape has changed totally", with the former Manchester United defender claiming the club are unable to attract star players like previous years.
United invested heavily to recruit Anthony Martial, Memphis Depay, Morgan Schneiderlin, Matteo Darmian and Bastian Schweinsteiger to Old Trafford, though a marquee signing did not materialise having been linked with moves for Gareth Bale and Thomas Muller.
Transfer target Pedro opted for Chelsea, while Louis van Gaal and Co. were also unable to retain the services of British-record signing Angel di Maria, who departed for Paris Saint-Germain after just one season.
Ferdinand became the most expensive defender in Premier League history at £30million when he moved to Old Trafford from rivals Leeds United in 2002, but the 36-year-old doubts whether he would choose the same club again this time around.
"When United came in for me there were other clubs who potentially wanted me... Barcelona, Real Madrid, Roma, Chelsea," said Ferdinand
"But my whole thinking was trophies. It wasn't about how much money I was earning, it was: 'Who is going to get me to win trophies in this country?'
"That was Manchester United and Alex Ferguson. That's all I cared about and the rest is history.
"Nowadays, United are competing against Manchester City, who have got more money, against Chelsea, who have got as much money or more, and can offer living in London and are going for titles. Then you've got Real Madrid and Barcelona as well."
Despite splashing the cash, United failed to reinforce the centre of their defence, having missed out on reported targets Sergio Ramos and Mats Hummels.
Midfielder Daley Blind has since been used as a makeshift defender alongside Chris Smalling and Ferdinand added: "I was talking to Nemanja Vidic the other day and we were both saying the change is unreal in terms of the personnel and transfer policy.
"We were saying, 'If they'd spent £50m when we were there, how much more would we have won!'
"You think, 'you've spent all that money, but where's your centre-half? Because you didn't buy Daley Blind as a centre-half, you bought him as a holding midfielder or a left-back initially, but he has now become a mainstay at centre-half'.
"Blind is a fantastic all-round footballer, but he is not a defender, not a centre-half. He is not going to spot the dangers as quickly as a natural defender."
