Britain's Brian Cookson is the new president of the International Cycling Union (UCI) after ending Pat McQuaid's eight-year tenure in an election in Florence.
Cookson, 61, defeated his Irish rival by 24 votes to 18 following a bitterly fought campaign.
The vote was held on a dramatic day at the UCI Congress in which the governing body's 42 delegates debated exhaustively about whether incumbent president McQuaid's disputed nomination should be allowed to stand.
In the end, Cookson took the brave step of calling a vote regardless and the gamble paid off in the form of a majority victory.
He said afterwards: "It is a huge honour to have been elected president of the UCI by my peers and I would like to thank them for the trust they have placed in me today.
"My first priorities as president will be to make anti-doping procedures in cycling fully independent, sit together with key stakeholders in the sport and work with Wada [the World Anti-Doping Agency] to ensure a swift investigation into cycling's doping culture."
Following his triumph, Cookson confirmed he would step down from his position as president of the British Cycling, a role he has held since 1996.
His victory brings to an end of one of the most controversial periods in cycling history, during which the Lance Armstrong affair unfolded and McQuaid and his predecessor, Hein Verbruggen, have repeatedly been accused of corruption.
Cookson and McQuaid were the only two candidates in the election, but the validity of McQuaid's nomination was a source of dispute right up until the last moment.
He had not been nominated by either his home nation, Ireland, or country of residence, Switzerland, which is demanded by current UCI election rules.
However, an amendment to the UCI Constitution was put forward by the Asian Cycling Confederation and Malaysian National Cycling Federation earlier in the summer suggesting candidates could stand if they had been nominated by any two national federations.
McQuaid subsequently received nominations from Morocco and Thailand and the election was allowed to go ahead under the condition that the amendment to the rules would be voted on just before today's election.
However, that vote was postponed today amid concern that rules should not be changed on the day of an election.
Lawyers were then brought into the congress to argue the validity of McQuaid's nomination under existing rules, but their case was vocally opposed by delegates.
Cookson ended the farcical scenario by unofficially accepting McQuaid's nomination and asking delegates to vote, and they subsequently backed the Briton.
Cookson added: "The campaign to get to this point has been intense but I am under no illusion that the real work starts now. So I call on the global cycling community to unite and come together to help ensure that our great sport realises its enormous potential. This is the vision that will drive and focus my activities over the next four years."