Okon slams McClaren's management skills
The Australian midfielder was largely out of favour under McClaren, and ended his Teesside misery by signing for Watford during the week.
Okon, who joined Boro from Fiorentina in the summer of 2000, has now ended his silence, claiming McClaren continually ignored him and feels he could hinder the Riverside outfit reaching the next level.
An unhappy Okon said: "In 10 years as a professional footballer, I have never been treated with so much disrespect.
"McClaren completely ignored me but I deserved better after helping them stay up."
Despite his unhappiness with McClaren, Okon seems to have been happy with life on Teesside.
"If anyone deserves success, it is Middlesbrough," added the 29-year-old. "Especially the chairman Steve Gibson.
"Have a look at what Bryan Robson did when he was manager. He took the club to another level and now it needs to be taken on again.
"Steve McClaren is a good coach but his management skills leave a lot to be desired.
"I would rather not say what I think of him as a bloke. He can do good things for them as a coach but as a manager I think the results will speak for themselves.
"Before the season began, he said I was one of five players he wanted to build the team around. That was never the case.
"After playing all the pre-season games, I never got a look in and was made to train with the reserves. Not only that, he completely ignored me.
"He hardly spoke a word until I got back from playing for Australia in the World Cup qualifiers.
"Then he apologised. He told me he`d made a mistake and insisted I would feature in the first-team plans. But then there was nothing, he never spoke to me again. I couldn't work it out.
"Now I just want to start my career again at Watford."