Carlton board member Craig Mathieson has quit after a heated verbal exchange with the club's president in the change rooms after the team's loss to Sydney.
The Blues issued a short statement on Monday, offering no explanation as to why Mathieson had resigned midway through the season.
ABC Sport understands Mathieson's resignation followed an argument with Carlton president Luke Sayers in the Blues' change rooms after Friday night's SCG loss to the Swans.
Mathieson was told the spat was unprofessional and did not meet the standards befitting a director
His position was not due to become vacant until the end of next year.
After narrowly missing the finals last season, Carlton started this season with great expectations about returning to the top eight for the first time in a decade.
But after starting the season with a draw and three wins, the Blues had a terrible opening quarter against Adelaide in Gather Round and have struggled since.
Their only win in their past seven matches was against injury-ravaged bottom club West Coast.
And Carlton have a daunting three weeks at the MCG ahead of their mid-season bye, starting with Friday night's match against Melbourne.
The match looms as pivotal for both teams, with the Demons having lost their past two.
Then comes the clash with fierce rivals Essendon, followed by a danger home game against Gold Coast.
Mathieson's uncle Bruce is a long-time Carlton powerbroker, and a fortnight ago he fiercely criticised the club administration.
Craig Mathieson was a club director for 11 years and oversaw its finance and audit remits.
"We accept Craig's decision to resign from his role as a club director and thank him for all he has contributed to the Blues across 11 years of service," Sayers said in a club statement.
Carlton said they would now look for someone to fill Mathieson's spot on the board.
ABC/AAP