The Chelsea midfielder ruptured his anterior cruciate ligament at the start of pre-season training and initial estimates were that he would be sidelined for most of the 2011/12 campaign.

Essien has not enjoyed the best of luck with injuries and admits it has been difficult to set out on the rehabilitation process once again.

However, he is working as hard as possible to return to action and is keeping a positive frame of mind.

The 28-year-old Ghana international wrote on in his blog on the official Chelsea website: "The injury is well-documented so I will not dwell on it, however I can say I have had a good operation on my knee and I am definitely on the mend.

"My days are filled with physio sessions from 10am to 5pm and it is a gradual process which I am confident will lead to the results I want.

"I have been here before and know the routine inside out now but it's still hard work as I hate to watch games on TV.

"I prefer to be with my team-mates in training and on the field of play, however I know I have to be patient so I can heal properly."

Essien added: "I have been asked when I am coming back and at this point in time it's down to how the recovery goes and when I am given the all clear by the medical team.

" I can't be more precise, but it's too early to give specific dates."

Andre Villas-Boas is confident Chelsea are capable of beating Barcelona and says he would quit if he did not feel his team could match the European champions.
Winning the UEFA Champions League has been a burning ambition of Blues owner Roman Abramovich, but the club have reached the final only once when losing on penalties to Manchester Unitedin 2008.

In contrast, holders Barcelona have won the competition three times in six years and have bolstered their squad further by signing Alexis Sanchez and Cesc Fabregas this summer.

Barcelona are again favourites to be crowned Europe's best, but new Chelsea boss Villas-Boas would have no fears about pitting his wits against one of the best club sides of all time.

"Barcelona are the reference," said Villas-Boas.

"They can beat any team in the world, but so could Chelsea and so could Real (Madrid).

"If I didn't believe that, I'd quit the game. I'm not going into the game with a losing mentality."

Chelsea managed to get the better of Barca more than once while Villas-Boas was part of Jose Mourinho's backroom team, while Mourinho's Inter Milan also beat them two seasons ago.

And Villas-Boas pointed out the competition was littered with upsets, including when he helped Porto triumph in 2004.

"That's what happened with Porto and Monaco," he said.

"Porto put out Deportivo and Lyon, and (Manchester) United in the last 16. Monaco put out Chelsea and Real Madrid.
"It's pretty unpredictable. There's a pattern over the last four years with more or less the same teams present in the semi-finals, but it depends on the draw up to then."