Pearson arrived at the club two years ago and employed Nigel Clough
Derby County have announced chairman of football Adam Pearson is to leave the club to "pursue new challenges".
The ex-Hull chairman has been at Derby since October 2007, and appointed Nigel Clough as manager in January 2009.
A Derby statement said the decision was "reached through mutual consent" and Pearson will be replaced by chief executive and president Tom Glick.
Pearson said: "I have enjoyed my two years at Derby despite not achieving the playing success we had hoped for."
Derby, who were relegated from the Premier League in Pearson's first season at Pride Park, currently sit 19th in the Championship but Pearson feels he leaves with the club in good shape to progress under Clough's tutelage.
"It has been an absolute pleasure and privilege to work with Nigel Clough over the past 10 months," he added. "He is a manager in whom the supporters and Board can totally trust with the future of their club.
"I have no doubt at all that Nigel, supported by his staff, will go on to be a truly great manager for this football club and create his own legacy, in the footsteps of his father [Brian].
"Under Nigel Clough's management the wage bill is now under control, the squad size is under control, the Academy structure is solid and we have a management team in place who will take the team forward."
Pearson bought Hull in 2001 when they were near the bottom of what is now League Two and in administration.
He left in June 2007 after two promotions had seen the Tigers climb to the Championship and, following his departure from Derby, has been linked with a return to the KC Stadium with the future of Hull chairman Paul Duffen in doubt.
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