Sunderland chairman Ellis Short has hit back at fans' criticism of his investment in recent seasons.
Short, 54, was the target of chants from Sunderland supporters during the Black Cats' disappointing 3-1 defeat at home to Norwich last Saturday.
Ex-Sunderland defender Michael Gray, who made 363 appearances at the Stadium of Light, also claimed that Short had lied to fans and failed to deliver what had been promised in terms of transfer funds.
"For the last five years, he has been lying to the fans," said Gray.
"He has promised players every single transfer window, they haven't come in, and the players that have been brought in have been has-beens."
However, Short, who took over Sunderland in 2008, responded to the criticism, denying claims that he lacks ambition for the club.
"I normally don't respond to criticism, but based on some recent comments, I feel that there are some points I need to address for the benefit of the fans," Short said in his programme notes for Saturday's home game against Swansea.
"First of all, no one who knows me or knows anything about me would say that I have no ambition for the club. That ambition certainly has not been realised yet, but it does not mean that I don't have it.
"Secondly, the assertion that I have been unwilling to spend money to fulfil the ambitions of the club and its fans is completely wrong. Every penny that comes from TV income and other commercial activities is spent on operating the club - that is, buying players, wages, and other associated costs.
"I have never taken money out of the club. In fact, I have funded significant shortfalls each and every season."
Short conceded that the club's transfer funds had been spent poorly in recent seasons, but also went on to claim that without his investment Sunderland would have been relegated from the English top tier.
"Since I have been involved, the good news is that my investment has kept us in the Premier League for nine consecutive seasons," he said.
"The bad news is, for the amount of money spent, we should be better than we are and no one knows that more than me.
"Has the money been spent effectively? No - that much is clear and ultimately that is my fault. But it is not a result of a lack of ambition or commitment."