ANDRE Villas-Boas admits Chelsea are expecting to tie-up a deal for a new centre-back when the transfer window opens a week on Sunday.

The Blues boss is searching for a new defender with Brazilian international Alex expected to leave Stamford Bridge after falling out of favour.

Bolton’s Gary Cahill is in the last year of his contract at the Reebok Stadium and Villas-Boas has already confirmed his interest in signing the England star.

And the Chelsea chief is says he is looking to bring in new blood at the start of the window rather than a repeat of last January’s deadline day purchases.

Villas-Boas said: “We are in the market for another centre-half and we have to respond quickly when the transfer window opens.”

Cahill’s expiring contract is expected to see his value reduced considerably from figures quoted in the summer, with the 25-year-old expected to command a fee in the region of £8million.

"We are aware of Gary's contractual situation," Villas-Boas admitted earlier this week. "He's an interesting player for the club.

"We haven't decided yet what we are going to do with the Alex situation. We have to make the wisest decision, be it Alex, be it Cahill."  

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