Hart said there was no question Dooley has improved the program since he took over the football program, especially give the many challenges he faced after taking over a program that was in disarray.
"Quite honestly he was given a very short stick to take into battle," Hart said.
Dooley was hired four days after Lane Kiffin's sudden departure in January 2010 after just one season. The next coach will be Tennessee's fourth in six years.
"This team was close to having a very good season. They never came unglued, they never pointed fingers," Hart said.
"We will now move forward to securing the best coach we can," he added.
Hart said he did not expect to use a search firm to aid in finding a new head coach.
"We want a coach who knows how to be successful and knows the difficulty of climbing the ladder in the SEC," Hart said. "We want somebody with integrity. We just had our probation extended. We don't have any margin for error. We have to have a culture of compliance. That is the number one priority in our athletics department."
Dooley did not appear at the media briefing Sunday afternoon. In a statement released by the university, Dooley said, "I am sorry we could not generate enough wins to create hope for a brighter future. Although progress was not reflected in our record, I am proud of the strides we made to strengthen the foundation for future success in all areas of the program."
"Derek is not at all bitter," Hart said about Dooley's reaction to being fired. "He talked about the players. His concern was the players and not himself."
Dooley was Tennessee's 22nd head coach. His record during his three-year tenure was 15-21. That includes a 4-19 won-loss record in Southeastern Conference play.
The Vols have lost 14 of their last 15 SEC games.
Under Dooley's leadership the Vols were 0-15 mark against Top 25 teams.
Previous reports indicate Dooley had a $5 million buyout clause in his contract. If other coaches are released from their contracts, the university could be required to make an additional $2 million in buyout payments.
Dooley came to Tennessee after holding dual positions of head football coach and athletics director at Louisiana Tech.
KNOXVILLE (WATE) - The fax machine in the University of Tennessee Athletics Department was humming Wednesday morning as high school and junior college football players sent their national letters of intentMore >>
The fax machine in the University of Tennessee Athletics Department was humming Wednesday morning as high school and junior college football players sent their national letters of intent to play for the Vols.More >>