Hiddink quit his post as manager of the Turkish national side last week, and following a successful six-month spell with the Blues in the 2008-2009 campaign, speculation has been rife over whether the Dutchman could return to the club.

However, Villas-Boas has made it clear that while the former Russia boss made an impact during his time at the club, the position of manager is filled.

"Guus had a very important period at the club and made the necessary changes first to take this club to another semi-final, plus an FA Cup and a good period of only one defeat in 15 games," he said.

"But it was six months at the club. It does not mean that he can always be as successful as that in a club of this dimension of tremendous expectations."

"Guus is one of the top managers in the world, a manager that is always available when a top team arises but at the moment this is not a vacancy, so it is not a vacancy to be taken, but when it is a vacancy I am sure he will be one of the top candidates."

There have been reports that Hiddink could be handed a director of football role by club owner Roman Abramovich, but the former Porto manager claimed that this is not something that he is aware of.

"It is not the instructions that I have from the club. It is not structurally even thought about within the club," he said.

Meanwhile, Villas-Boas has clarified comments made about the refereeing of Chris Foy in Chelsea's 1-0 loss to QPR last month.

Villas-Boas has been charged with improper conduct after an outburst towards Foy but the Portuguese manager says he was questioning only the consistency of Foy's decision-making, not his integrity.

"My words were that the referee has set out a criteria on the decision-making that he didn't take through the whole game for both teams, not that he was privileging one team," Villas-Boas said.

"But that decision-making that he took, he didn't apply it throughout the whole game in different types of situations, and even for both teams. So there wasn't a pattern in his decision-making when he set out that pattern, so I have to deny the charge, because the charge implicates that I called the referee biased and that I was questioning his integrity."

"I was not questioning his integrity, I was questioning that when he was making a pattern of his decision-making, he didn't take that pattern throughout the 90 minutes of that game."