Middlesbrough chairman Steve Gibson has revealed boss Aitor Karanka left of his own accord after struggling to keep the Teessiders out of the relegation places.

Gibson told the Times: "I know people are cynical when you say that a decision was mutual, but he wasn't sacked. He sacrificed himself.

"He's in a good frame of mind. I think he's relieved. He has been enormous for our club. He has progressed us and he will have learnt an enormous amount from this experience.

"He's got a wonderful future in football – I really think that."