Andre Villas-Boas says Chelsea are considering bringing two players in during the transfer window but are wary of January signings.
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Chelsea are currently fourth in the Premier League, nine points behind leaders Manchester City, and have already allowed Nicolas Anelka to leave the club this month, with Alex set to follow.
The Blues have made central defence a priority, and have already agreed a fee with Bolton for Gary Cahill, but Villas-Boas has confirmed he would be open to signing another player to strengthen another area of the field.
"Apart from a central defender, we might get one more player in, but we're not sure yet," Villas-Boas said. "It's always difficult. The top talent is normally cup-tied in the Champions League or in different domestic competitions and it's difficult for the selling club to make players available.
"It's normal that you struggle in the transfer market. Normally it's a market where you overpay a lot and that's what we don't want to do now. That's why we have set out not to do a lot in the transfer window."
Meanwhile, winger Florent Malouda - who has been linked with a move to Paris St Germain this month - has rejected the idea Chelsea are in a transitional period.
"I don't like this expression of transition," he said. "When you play for Chelsea there is no transition because everyone expects the best from the squad we've got. There is a lot of talent and ambition.
"When you sign for the club, it doesn't matter who the players or manager are - all you expect is to win trophies. There is a mentality here. I think that's what the fans expect from us as well. We should not look at all the changes as an excuse. We must contend to win trophies year after year.
"The newer players have settled very well in the team. Everyone is focused on the club objectives and are sad when we don't have the results we expect. We're always trying to turn things around and we know how fast things can change.
"We know when we don't have results, doubts are coming from the outside so we have to stay strong as a squad to be able to compete for trophies. We have to go for it."
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