Europe Tour de France champ Alberto Contador vows to challenge doping verdict

The controversial conviction of Spanish cyclist Alberto Contador, together with the US decision to drop a Lance Armstrong investigation, highlights the political and legal challenges of cleaning up sport.

Juan Medina/Reuters

Three-time Tour de France champion Alberto Contador signaled today his intention to appeal the doping conviction handed down yesterday by the Court of Arbitration for Sport (CAS) after a grueling 18-month legal battle.