Juan Mata has admitted that the whole Chelsea squad are fighting for their futures at the West London club.
The Spanish midfielder claims that he and his teammates must prove themselves ahead of a rumoured busy summer in the transfer window for the Blues.
Mata said: "We have to prove ourselves every game.
"For me and the other players, we are playing in a top squad and a top club and we must always do our best in every game.
"Roman told us that we have an opportunity to change this run of defeats and against Birmingham we did, so we have to keep going and try to get better."
Mata scored during the 2-0 FA Cup victory over Birmingham on Tuesday evening.