The former Real Madrid man, who has also been linked with Arsenal and Tottenham, is believed to be on the verge of signing at Stamford Bridge for a fee in excess of £23m.
However, the 23-year-old has insisted that he can continue to improve at the Mestalla.
"Moving can certainly be a positive experience but the truth is I do not know when I will. I have not raised the issue," Mata is quoted as saying in AS.
"The day I left Madrid for Valencia was very important, with that fear in you that things may not go well.
"I have grown a lot as a player here and, frankly, I think I can keep growing."
The Andalusian club were scheduled to travel to Osasuna this weekend, but the game was postponed following the player strike in Spain.