With £8.3 billion shared between the 20 Premier League clubs after the sale of their global television rights, plus a host of new owners at home and abroad, competition for players, they concluded, would be fierce.

A month in, and they have been proved right.

Look at their efforts to sign a new defensive midfielder. United hold an interest in Eric Dier but despite being able to pay over the odds and double the 23-year-old's wages at the drop of a hat, Tottenham can afford to stand their ground. And all while building a new stadium which could cost £800 million.

Sources have told ESPN FC Dier would be open to a move to United, but that doesn't matter. It was a different story in 2006, when United signed Michael Carrick, or Dimitar Berbatov in 2008.

It led Mourinho to say in an interview with France Football in March that United may never sign another player from Tottenham, or any of the Premier League's top six. There is a feeling at Old Trafford that could easily be extended to the top 10.

Nemanja Matic may turn out to be an exception but only because Chelsea are willing to let the Serbian leave if they sign Tiemoue Bakayoko from Monaco. If the figures for the two deals right, Chelsea could end up replacing a 28-year-old with a 22-year-old and still make a £5m profit. Mourinho, meanwhile, will get a midfielder he knows all about, one who is proven in the Premier League and has helped win the title twice in the last three years.

United wanted four key signings in place before the squad reported back to Carrington on July 8. But with just two weeks to go, only Victor Lindelof has arrived. It is no coincidence that negotiations with Benfica for the Swedish defender began in December. Although plans for a January deal were eventually scrapped, it gave United a head start this summer.

Woodward and his team are battling against a group of rival clubs that, according to those inside Old Trafford, is growing every year.

Everton have not been considered genuine competition since the 1980s but already this summer they have spent nearly £30m on Jordan Pickford and more than £25m on Davy Klaassen. They can also hold firm in their demand for £85m for Romelu Lukaku. There is a genuine feeling at United that Everton could break into the top four next season if they sign the right players and keep Lukaku.

On top of that, AC Milan and Inter Milan both have new investment from China. Inter have so far refused to budge on their €50m valuation of Ivan Perisic, despite struggling to comply with financial fair play regulations. The same Perisic, who, in January 2013, left Borussia Dortmund for Wolfsburg for €8m. United are no longer just competing against Barcelona, Real Madrid, Bayern Munich and Chelsea.

Mourinho said as early as February that he did not want Woodward to pursue "impossible" transfers. Without naming names, he was talking about Neymar, Sergio Ramos and the other long-shots the club have been linked with summer after summer. But even deals for the likes of Dier and Perisic -- straightforward in the past -- are falling into the same category.

Privately, agents, intermediaries and club officials have all called the market "crazy". And United, even with their vast resources, are feeling it as much as anyone.

It is one of the reasons they have turned to Javier Ribalta, who earned a reputation for finding value where others couldn't as scouting manager at Juventus. Woodward and Mourinho predicted a tough transfer window. Still, it is perhaps even taking them by surprise.

With lists of options for each position to be strengthened, Mourinho is still likely to get his four signings. But they will come at a cost.