Eden Hazard would cost the best part of £100m, if Chelsea were open to selling him, Jose Mourinho said yesterday.

The Belgian winger has been one of Chelsea’s best players this season, and Mourinho pointed to a marked improvement in his application in training and in the defensive side of the game.

Chelsea paid Lille £32m for Hazard in 2012. Mourinho said that he was two or three times the player now and that his value should increase accordingly, although there was “no chance” of the club selling him. “I think his progress is in everything,” Mourinho said. “He was not voted, but he was known as one of the worst trainers. He has become, I don’t say one of the best, but a good professional in training.”

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Hazard is now far more efficient on the pitch, making more use of his talents throughout the 90 minutes. “He was known by lots of quality – which he keeps – but not being very effective in terms of real production,” Mourinho said, “and at the same time, without that culture of knowing how to defend as a team. He has improved in every aspect.

“Now he works very hard for the team, he wants the initiative of the game. He does not disappear after doing something, to reappear after 30 minutes, to show that fantastic ability – he wants to be influential all game. He now has the idea that ‘I am a top player and I have to be there every match’.”

Hazard is also starting to learn his defensive responsibilities, the Chelsea manager added. “He is very strong physically, he does not look it but he is. It is more from a mental point of view, but he is doing that. He knows where he has to cover, close down areas. We are very happy with him.”

This does not necessarily mean he loses his attacking edge. “It’s never a problem for a person to be more complete than before. Because you work with a computer, your handwriting doesn’t have to be terrible.”

Mourinho has seen Hazard start to take more and more responsibility, and over 2014 there will be more opportunities on the biggest stages for him to assert himself.

“At Derby [in the third round of the FA Cup] he came off the bench and immediately you could feel that he was on the pitch. He’s the kind of player we want. It has been a fantastic evolution for him. Now he is playing in the Champions League knockout phase, with real pressure on him, plus he will have the experience of the World Cup. So at 23, to be where he is, you can only expect it to get better.”

Kevin de Bruyne is close to an exit from Chelsea after Mourinho confirmed the club are on the verge of agreeing a fee with two unnamed clubs for the Belgium forward.

“He has a chance to go,” Mourinho said. “We had two bids from two different clubs for Kevin. That’s what the club is analysing.

“[A fee is] not agreed, but I believe that between our club and the other club we will reach an agreement. The interest is big from the club, even bigger from the player.”

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