Southampton have confirmed the departure of chairman Ralph Krueger.
The Canadian-born German former professional ice hockey coach was set to be out of contract at the end of June.
Press Association Sport understands Krueger, 59, has left his position with immediate effect.
A club statement read: "The shareholders and everyone involved with the club would like to put on record their thanks for Ralph's leadership, dedication and hard work over his six years with Southampton."
Southampton added "more information about the future leadership structure" of the club would be released at the end of the season.
The statement continued: "For now, all our efforts and focus are on a strong finish to the season and remaining within the Premier League.
Krueger joined Southampton in 2014 and helped stabilise the club in the Premier League.
"Everything has a beginning and everything has an end. It is the journey in-between that I will treasure. Thank you Southampton Football Club for the journey," Krueger said.
Majority shareholder Gao Jisheng praised Krueger's work. He said: "Ralph represented our club with honour and integrity, and followed 'The Southampton Way' with great passion.
"We thank him for the foundations he has helped to build and wish him well for the future."
Fellow shareholder Katharina Liebherr added: "Ralph laid the foundations for the Saints to be a sustainable team that put pressure on the top sides in the Premier League.
"I, along with my family, will always be grateful for all that Ralph has done for the club."