He said: "I have only once said that I wanted a change, a year ago, after the departure of Mourinho.
"I didn't like the atmosphere at the heart of the club and I had the courage of my convictions.
"Two years ago, I scored 32 goals in a season - did you hear me asking to leave then? No.
"I am like any other goalscorer, happy when I am hitting the back of the net."