Andre Villas-Boas yesterday received more backing from his former club Porto as speculation continued over the Chelsea manager's future.

Villas-Boas, whose attempts to turn the Blues' season around were supported earlier this week by the Porto president, Jorge Nuno Pinto da Costa, was given words of encouragement by the man who succeeded him at the Estadio do Dragao.

Vitor Pereira, who was Villas-Boas's assistant during Porto's record-breaking, quadruple-winning 2010-2011 season, issued the praise as he prepared his side for tonight's Europa League last-32, first-leg match against Manchester City.

As well as previewing that game in his pre-match press conference, Pereira spoke about his predecessor's troubles at Chelsea, suggesting that Villas-Boas needed to be given time to transform his new club's fortunes.

The Porto coach said: "Andre is a quality coach and will certainly, in time, prove his quality and competence." Pereira's backing came as reports continued to claim that some of Chelsea's players had lost faith in Villas-Boas.

It was suggested yesterday that senior Chelsea squad members were hoping that the club's owner, Roman Abramovich, would once again bring in Guus Hiddink to save the club's season, just as the owner did three years ago. Chelsea have repeatedly maintained that Villas-Boas's position is not under threat, while Hiddink's agent has insisted his client would not comment on whether he would consider returning to Stamford Bridge unless a vacancy arose.

The Dutchman was certainly a popular figure among the players during a caretaker spell in 2009, during which the club lost just one match and won the FA Cup. Villas-Boas, on the other hand, was reportedly challenged openly by members of his squad during frank exchanges at the club's training ground on Sunday.

The former Chelsea manager Luiz Felipe Scolari suggested player power was one of the reasons he was sacked and replaced by Hiddink in February 2009, while Pinto da Costa claimed that previous Chelsea manager Jose Mourinho's continued contact with his former stars was undermining Villas-Boas.

Abramovich has been far more reluctant to bow to any suggestion of dissent in the ranks since Villas-Boas took charge, giving the Portuguese the green light to revamp an ageing squad.

But the transition has proven a turbulent one and it remains to be seen whether Abramovich will fire another manager if the Blues continue to look in danger of failing to qualify for the lucrative Champions League. The Russian will also be expecting progress in the FA Cup on Saturday, when Chelsea host Birmingham, and it will not go down well if they fail to get past Napoli in the Champions League.

Chelsea's captain, John Terry, is close to a comeback from a knee injury but Ashley Cole remains a major doubt for the FA Cup game with a calf problem that has left him unable to train since last Saturday's Premier League defeat at Everton.

Thibaut Courtois, Chelsea's summer signing, has revealed he wants a loan move to another English club before making his Chelsea debut. The goalkeeper, who joined Atletico Madrid on a season-long loan upon moving to Stamford Bridge from Genk, said: "I think that before going to Chelsea, I have to play one or two years in another English team to discover the football played there.

"After that, we'll see if I am ready to move to Chelsea. It's hard to say now."

There would be no shortage of suitors for Courtois, who has earned rave reviews in Spain. He told a Belgian radio station: "At first it was difficult. When I arrived, I found myself alone at the hotel. I almost wanted to cry. My team-mates helped me. I learnt the Spanish language and all is well now. If Madrid wants me to stay one more season and Chelsea accept, we'll see."