Defender Ricardo Carvalho insists Chelsea's recent form will have sent a message of intent to their title rivals.
The Portugal centre-half also maintained Chelsea's performances during January proved they could cope without their African Nations Cup quartet of Michael Essien, Didier Drogba, Salomon Kalou and John Mikel Obi.
However, Carvalho is well aware playing well will mean nothing unless the Blues can win some silverware under new coach Carlo Ancelotti.
"We are playing well but in the end you have to win trophies," he said.
"Everyone knows how important the league is for us and we want to be at the top and we want to stay there until the end.
"The message to the other teams now is they have to be worried about us because we have got great players here and we are fit and wanting to play well and help the team to win the trophy.
"Everyone was speaking a bit too much that we could miss the Africans but we have a strong squad with players who want to play as well. They showed everyone that they have got quality to play.
"Now it is welcome to Didier and Salomon. They are important players and they are good to come back. In February there are a lot of games and they can help us."
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