Chelsea boss Andre Villas-Boas has confirmed the club have tabled a bid for Porto wideman Alvaro Pereira - although he is not confident the player will join before the end of August.
Reports suggest Chelsea have had a £16.6 million offer turned down, with Porto holding out for an amount closer to £26m - the release fee stipulated in the Uruguay international's contract.
"The only thing I can confirm to you is that we have made a bid for him and we are very far apart in terms of numbers," said Villas-Boas.
When asked if he was confident a deal could be done, he added: "Not very confident."
Pereira, who can operate on the left side of defence or midfield, looks a natural replacement for Russia international Yuri Zhirkov, who returned to his homeland earlier in the summer.
He rose to prominence when playing under Villas-Boas at Porto last season, but his value soared when he impressed during Uruguay's victorious Copa America campaign.
Pereira's arrival would push Florent Malouda, a target for Juventus, further towards the Stamford Bridge exit door. Malouda's claim to a first-team place has already been dented by the £23.5m arrival of Juan Mata, which was confirmed on Wednesday.
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