The 32-year-old has not played in the current season due to persistent Achilles trouble and underwent an operation in August.

Parker played through the back-end of last season receiving injections to ease the pain of the problem.

And Villas-Boas has revealed the Englishman is still struggling to overcome the problem.

"It's difficult for him as he still feels pain and is still disturbed in his recovery," Villas-Boas told reporters.

"It prevents him from being on the pitch but he has been evolving inside, in the gym, with the medical department.

"It is still within the limits of what we expected. He is making good progress and there has been less pain.

"It will take two or three weeks - we could be looking at Christmas. Hopefully less."