Nairo Quintana has lodged an appeal against his Tour de France disqualification for taking a banned pain medication with the Court of Arbitration for Sport, the tribunal announced Thursday.
The Colombian was stripped of his sixth-place finish for taking tramadol, a synthetic opioid which has been on a list of cycling's prohibited substances since 2019.
"At this time, it is not possible to indicate when the final decision will be announced," the court said in a statement.
A panel of arbitrators must be appointed before the date for a hearing can be set.
Traces of tramadol and its two main metabolites were found in two dried blood samples provided by Quintana on July 8 and 13 during the Tour, the International Cycling Union (UCI) said last month.
As a first-time offender, he was not banned from further competition and had been free to compete in the Vuelta a Espana.
However, the 32-year-old withdrew from the race the day before it started, saying he did not have "the head or the body for competition".
Quintana was the first Colombian to win a Grand Tour when he claimed Giro d'Italia glory in 2014. He triumphed in the Vuelta two years later.