The International Cycling Union (UCI) is to open an investigation into allegations that Olympic champion Alexandre Vinokourov of Kazakhstan bribed Russian Alexandre Kolobnev to win the 2010 Liege-Bastogne-Liege race, the governing body said on Monday.
Vinokourov won the one-day race by beating Kolobnev in a two-man finish.
The investigation is starting because the UCI has received a case file from an Italian public prosecutor who is investigating alleged corruption in cycling.
"Now, in the light of this additional information we received last week from the Italian prosecutor we are opening an investigation into the matter," UCI President Pat McQuaid told Reuters.
"Both riders have been summoned to UCI headquarters.
"If Vinokourov and Kolobnev were to be proven guilty the license commission would re-evaluate the world tour licenses of the Astana and Katusha teams."
McQuaid said Padua prosecutor Benedetto Roberti had passed on details from the case he is working on.
"We would welcome any other information from this investigation," said McQuaid.
According to email exchanges between the two riders published by the Corriere della Sera newspaper on Saturday, Vinokourov agreed to pay Kolobnev 150,000 euros for the win.
It was the Kazakh's biggest victory since his comeback from a two-year ban he was handed for testing positive for blood doping on the 2007 Tour de France.
Vinokourov has been appointed Astana team manager for the 2013 season.
Cycling is reeling from the Lance Armstrong scandal in which the American stripped of his record seven Tour de France titles for using performance-enhancing drugs and organising doping.