The job Mauricio Pochettino has done at Tottenham during his four years in charge has been nothing short of miraculous.

He has transformed an inconsistent side into top four regulars, playing some of the best football in the Premier League along the way.

The Argentine has achieved it all on a shoestring budget as well, with Colombian defender Davinson Sanchez his most expensive purchase at around £40m.

While that figure is quite high, it's nothing compared to the likes of Manchester City, Liverpool and Manchester United,

However, with a new stadium being built and a lack of funds for transfers and wages, keeping Tottenham's star players may prove difficult in the coming years.

Harry Kane, Heung-Min Son and Dele Alli have all recently signed new deals, but the same cannot be said about Danish playmaker Christian Eriksen.

His contract only runs until the summer of 2020, with Real Madrid regularly linked with the 26-year-old.

And now, a source close to Eriksen has revealed what he thinks about his future.

According to Spanish publication AS, Eriksen's camp are not optimistic about a contract renewal, with the situation labelled as "very, very difficult".

While Daniel Levy is notoriously hard to negotiate with, he will be wary about Eriksen leaving on a free and it's believed the Dane will cost between £50-75m in the summer.

The Eriksen source also stated that the player "sees Madrid as a very big club. For him it would be a great honour to play in the Bernabeu. When we talk about great clubs, of course we talk about Madrid. It could be the first option.”

It's not sounding great for Spurs.

The north London club brought Eriksen in for around £11.5m in 2013 and he has gone on to become one of the league's finest midfielders.

Replacing a player with his talent will certainly not be cheap for Pochettino's side.