Doncaster chairman John Ryan has quit the Championship club, ending his 15-year association with Rovers.
Rovers have been in talks with Irish-led consortium Sequentia Capital over a possible takeover of the club.
But reports emerged that Ryan had fallen out with other members of the board over a meeting between Rovers and the consortium this week.
In a statement the club thanked Ryan, who took over when a Conference side in 1998, for his "outstanding work".
"We hope he will remain a close friend of the club and continue to show his support for Doncaster Rovers.
"Everyone at the club continues to work hard with the same ambition and drive as usual in order to achieve our aims and objectives."
His reign in charge of the South Yorkshire club has coincided with the one of the most successful eras in their history, including four promotions, a first major cup win in the Johnstone's Paint Trophy and a return to the second tier for the first time in half a century.
Sequentia, supported by a wealthy Belize-based tycoon, were first linked with a takeover of Doncaster in June following the club's return to the Championship, and a heads of terms agreement was reportedly signed by both parties.
However, the club began to distance themselves from Sequentia, and issued a statement saying Doncaster would remain in their current investors' hands in September.
But the consortium seemingly remain interested in securing the club, despite this setback.