The 22-year-old was widely regarded as the best youngster in Spain during his time at Racing Santander, where his performances earned him a move to Real Madrid in 2010.
A succession of serious injuries stunted his progress with the capital outfit, but the Spaniard has started to show glimpses of his former self for Valencia this season.
"I'm doing more all the time. I'm very self-critical of my own performances and I'm still not at my best. Both the team and myself, we're starting to improve," he told reporters at a press conference.
"I've always said that after so many injuries, it was very important to string together three consecutive games and play regularly. In my mind, that helps a great deal, to get back to my best level."
Canales, who is yet to win a full cap for Spain, initially joined Valencia on loan in 2011, before making the move permanent in 2012.