Ricardo Carvalho believes Chelsea's rivals for silverware should be concerned by threat of Carlo Ancelotti's side.
The Blues still have a chance of winning the Treble this season as they sit top of the Premier League, while they also remain in the UEFA Champions League and FA Cup.
Chelsea were expected to struggle in January without the services of African Cup of Nations participants Didier Drogba, Michael Essien, John Obi Mikel and Salomon Kalou but they arguably improved when demolishing Sunderland and Birmingham.
Carvalho does not think the foursome were especially missed and that his club's determination to win trophies, specifically the league, coupled with form and fitness should make their rivals anxious.
"We are playing well but in the end you have to win trophies," said Carvalho ahead of Saturday evening's trip to Burnley.
"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."