When it comes to keeping prize assets, the Premier League has suffered some significant setbacks in recent years.

For a competition that prides itself on being the best in the world, the departure of Cristiano Ronaldo from Manchester United to Real Madrid for a world record fee of £80million in 2009 was a major disappointment.

To make matters worse, the Spanish giants returned to these shores last summer to prise Gareth Bale away from Tottenham with a new world benchmark of £86m.

It has not been all doom and gloom. England’s top flight continues to attract and keep stars such as Sergio Ageuro, Luis Suarez and Yaya Toure, while Chelsea potentially have the most exciting of all in Eden Hazard.

The Belgium international was pursued by a host of Europe’s leading clubs in 2012 before confirming on Twitter he was joining the then ‘European champions’ from Lille for £32m.

He is less than two seasons into a five-year contract and already looks a bargain. In his first season he grew stronger as the campaign progressed and helped Chelsea win the Europa League.

Under Jose Mourinho, he is taking his game to a higher plain and even opposition managers have expressed their appreciation of his talents.

Chelsea’s top scorer on 11 goals, his performances are attracting covetous glances from abroad with Paris Saint- Germain and Real Madrid known admirers.

Hazard continues to express his happiness at Stamford Bridge but due to Ronaldo and Bale’s highly publicised departures from these shores, it means there will always be concern in the back of some Chelsea fans’ minds over whether the club will keep such a talent.

Mourinho knows all about the allure of wanting to test one’s ability abroad. After all, his ambition led him to manage Chelsea, Inter Milan and Real Madrid after guiding Porto to the European Cup in 2004.

During that time he has worked with some of the world’s best players and is in no doubt that Hazard will become one of them. But, crucially, he feels the Premier League is the best venue for him to achieve it.

In the second part of his exclusive interview with Standard Sport, Mourinho said: “This is the opinion of somebody who has been here in this country and worked elsewhere. For me the situation is clear — the best place to develop is in the most difficult League.

“After that the best place to show how good you are is in the easiest League, not in the most difficult.

“In England, you don’t do 100 points, you don’t score 125 goals unless Manchester City can do it this season. But normally the evolution of a player needs difficulty and the difficulties help the development of a player. You reach your maximum with difficult situations. The big push comes.

“After that you have choices, stay in the most beautiful League to play or go where it is easier to succeed.

“Of course it is easier to succeed abroad. You go to Spain and there are two big clubs [Barcelona and Real Madrid]; you go to Germany and they have one big club [Bayern Munich] and a little bit more. In Italy now there is one big team [Juventus are eight points clear in Serie A], although obviously more than one big club. So it is easier to succeed.

“If you are an attacking player and go to Barcelona or Real Madrid, it is easier to score 50 goals than if you’re playing in England.

“Of course these clubs are a big attraction. You can’t blame a player. As a manager I had that instinct, too. I wanted to go to Madrid myself.

“So if a player has that feeling it’s very understandable. But I keep thinking in my case, where I enjoyed most is where the competition is. It’s high here. If I was a player I wouldn’t leave the Premier League.”

One suspects Mourinho’s presence at Stamford Bridge will play a major part in ensuring just that because Hazard (right) is starting to revel under the 50-year-old’s guidance.

In the first few months of the campaign, the Belgian appeared to take time to adjust to his methods and tactical demands.

But in recent weeks the 23-year-old has been Chelsea’s stand-out performer, noticeably becoming a more complete player who is willing to track back as well as take on opposition defenders.

Such progress leaves Mourinho in no doubt what Hazard can achieve and he added: “Eden can become one of the best players in the world. Now he sees his football and profession with different eyes.

“He understood how there is a gap between the talent and the performance and a gap between the occasional performance and the permanent stability at a high level. He now understands how he can fill this gap.

“He trains much better, he concentrates much better. Tactically, he has had a big evolution. He understands how to put his qualities on the surface of the team. He understands the best way to hide his weaknesses.

“He is 23 and now in his second season in England after an experience in France. He is playing in a Chelsea side trying to win the Premier League, also the Champions League, and is going to the World Cup with Belgium. He has in his hands all the tools to fill these gaps.

“Everyone knows he is a talented player, that he was that when he arrived here. But now he is trying to go to a different level, we are helping him and he is doing it step by step. Hopefully, the big talent can transform himself into the big player.”

Chelsea fans are hoping that the Premier League will get to witness it.

Jose Mourinho is supporting Chelsea Soccer Schools which provide opportunities for players of all abilities in the South-East. The courses are available for both boys and girls and promote the Chelsea Foundation’s values of fair play and respect in a fun and enjoyable enviroment.www.chelseafc.com/soccerschools