Hein Verbruggen, a former president of the International Cycling Union, has died at the age of 75.
Verbruggen, who ran the UCI from 1991-2005, had been diagnosed with leukemia.
"I'm sad to hear of the passing of Hein Verbruggen and offer my sincere personal condolences to his family and friends," said UCI president Brian Cookson.
Dutchman Verbruggen was also a member of the International Olympic Committee from 1996-2008.
His time in charge of the UCI corresponded with a number of controversies
In 2015, the UCI-supported Independent Commission for Reform in Cycling (CIRC) concluded that, under Verbruggen, the UCI colluded with Lance Armstrong to cover up allegations the seven-time Tour de France winner had taken drugs.
Verbruggen strongly rejected those findings, describing the report as "unfair, biased and incomplete in its methodology, in its substance and in its conclusions".