Having worked under the Portuguese manager, the current Blues boss - who has only been at Stamford Bridge since the summer - is worried about his return to English football

Chelsea boss Andre Villas-Boas has sent out a warning to all top Premier League managers that their jobs are constantly under threat from Real Madrid head coach Jose Mourinho.

The Bernabeu boss has been linked with a move back to Stamford Bridge today and the 49-year-old has always said he would welcome a return to English football in the future.

Villas-Boas worked under Mourinho during his spell at the west London club but highlighted that he was still the top dog at Chelsea and dismissed any immediate return of the ‘Special One’.

“At the moment, there is not a vacancy at this club – that is the most important thing. And the Real Madrid manager is not available at the moment,” he insisted to reporters on Friday.

“He's tied to the best club in the world. The only thing I can say is that I have lived Jose's availability when we were out of Chelsea and we know and I know how many clubs came knocking on our doors.

“So, a manager of Jose's dimension and the number one in the world will always be an attractive target for whatever club.”

Villas-Boas was keen to add that Mourinho’s intent on returning to English football someday puts pressure on managers at all the biggest top flight clubs.

The 34-year-old coach added: “Because he's a manager that makes himself available to return to his beloved England will for sure capture the interests of City, United and Chelsea and Tottenham and Liverpool and Arsenal, and so on and so forth.

“So, in that sense, we are all under pressure, from Mancini to Ferguson to me to Dalglish to Harry Redknapp and so on.”