The International Cycling Union banned Alejandro Valverde from the Road World Championships on Wednesday and is asking for disciplinary proceedings to be launched into the rider's involvement in the Operation Puerto doping scandal.
The UCI said it requested that the Spanish Cycling Federation open proceedings against Valverde after concluding that the Spanish rider could have violated doping rules.
The worlds will take place in Stuttgart, Germany, from Sept. 26-30.
After "meticulously" examining a 6,000-page dossier from the Spanish district attorney, the UCI said it concluded "several documents may show the involvement of Alejandro Valverde in the affair."
"These proceedings would not imply any guilt on the part of Alejandro Valverde," the UCI said in a statement. "However, according to UCI regulations, and to safeguard the atmosphere and reputation of the World Championships, Alejandro Valverde will be prevented from participating."
If Valverde is found guilty, he faces a two-year ban and could lose a year's salary under the UCI's anti-doping charter.