The EPL referee was accused of saying “shut up you monkey” to the Super Eagles’ captain in 2012.
The FA accepted the player had believed the referee had racially abused him – but Clattenburg was found to have no case to answer.
Chelsea star Mikel was subsequently given a three-match ban and fined £60,000 by the FA for threatening behaviour.
In a rare interview, Clattenburg has spoken only about the incident and how it affected him.
He told AP: “It was a tough moment in life and the pressures were huge.
“It took me a little while to come back because I didn’t know if I wanted to referee or not because I lost the love for refereeing.
“I am strong willed now. I do what I believe is correct. I’m a professional but I have to make sure I apply my personality to the pitch because you have to have personality and not robots. Players want a little bit of personality.”