AIGLE, SWITZERLAND // The International Cycling Union (UCI) must decide by the end of today if it will ask sport's highest court to ban Alberto Contador for doping during the 2010 Tour de France.
The UCI is using the last day of its deadline to weigh up an appeal to the Court of Arbitration for Sport (CAS), after the Spanish cycling federation cleared Contador in February.
Contador tested positive for clenbuterol, a banned fat-burning, muscle-building drug, days before winning the Tour last July.
Spanish authorities accepted his explanation that he inadvertently consumed the drug in contaminated beef.
If the UCI appeals, Contador faces a possible two-year ban and losing his Tour victory. Contador can continue racing until CAS gives a verdict.
Contador said when exonerated by the Spanish federation that he believed its decision would "probably" be challenged.
Even if the UCI declines an appeal, the World Anti-Doping Agency (Wada) has a further 21 days to decide on pursuing Contador at the CAS.
Wada regards clenbuterol as a zero-tolerance drug, though its rules allow athletes to escape a sanction if they prove "no fault or negligence" on their part.
Contador had minute traces of the drug in his urine samples taken in the closing days of the Tour.
The UCI announced last September that Contador was provisionally suspended and asked the Spanish federation to investigate.
The federation's disciplinary committee originally proposed a one-year ban for Contador in January.
Contador's legal team then offered new evidence and he was cleared to race three weeks later.
Days before the decision, Jose Luis Rodriguez Zapatero, the Spanish prime minister, had said "there's no legal reason to justify sanctioning Contador."
Contador resumed his career with new team Saxo Bank-Sungard and has since completed two races. He was fourth in the Tour of Algarve in Portugal and won the Vuelta of Murcia in Spain. He leads the week-long Tour of Catalonia.
Contador is one of only five cyclists to win the three Grand Tours — the Tour de France, Giro d'Italia and Spanish Vuelta.
He also won the Tour in 2007 and 2009, and was prevented from defending his first title in 2008 because his Astana team was banned for doping offences at the previous year's race.
Only one cyclist has lost a Tour title for doping, when Floyd Landis was stripped of his 2006 victory.