Eamon Dunphy, the ghost-writer for Roy Keane's autobiography, claims Mick McCarthy only has himself to blame after resigning as Republic of Ireland manager.
Dunphy claims it was up to McCarthy to solve the dispute with Keane.
"The buck always stops with the manager in football unfortunately," Dunphy told Sky Sports News.
"It was harrowing for all people involved. Niall Quinn, Mick McCarthy, Roy Keane. It has been a very, very unhappy experience and it should never have got to this stage.
"Mick McCarthy was the person in charge of that situation and he should have managed it better."
Dunphy also denied the Irish media had "hounded" McCarthy out of the job.
"I think compared to the England media, the Ireland media are very fair," he said. "He hasn't been hounded out of the job. He became untenable because of the decisions that effectively he made himself."