Middlesbrough chairman Steve Gibson has revealed Aitor Karanka "sacrificed himself" after failing to drag the club out of their relegation tailspin.
The Spaniard parted company with Boro, who sit in 19th place in the Premier League table, on Thursday three years and four months into his reign following lengthy talks with Gibson.
However, the Teesside businessman has insisted the man who was mentored by Jose Mourinho at Real Madrid left of his own accord.
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."
Karanka's number two Steve Agnew has been placed in charge of team affairs ahead of Sunday's clash with Manchester United, and Gibson will not make any snap decisions over a long-term appointment with 11 games of the season remaining.
He said: "I've known Steve a long time. He's a very good coach and a very good number two. There's more to him than people know and a bit more steel.
"Steve could be a surprise number one. That may disappoint those people who want glamour and somebody to come in ready-made, a sexy name, but that's not what we need at this point.
"I want to find out about Steve."
Meanwhile, Middlesbrough have announced former Scotland striker Joe Jordan has joined the club to help caretaker boss Agnew.
Boro also confirmed goalkeeping coach Marcos Abad, analysts Juanjo Vila and Guillermo Salinas had all now left the club "as part of a backroom re-shuffle."