Spaniard Roberto Heras is to appeal against his two-year ban for using the banned blood-boosting drug EPO.
Heras was stripped of victory in the Tour of Spain as a result of his positive test
His lawyer said he was deciding whether to have the case heard in Spain or the Court of Arbitration for Sport.
"We need to study the decision carefully to see where we take the appeal," Jose Maria Buxeda told Spanish daily El Pais on Thursday.
Heras, 32, tested positive for EPO on he way to a record fourth triumph in the three-week Tour of Spain.
The Spanish Cycling Federation later stripped the rider, from Salamanca, of his victory and awarded the race to Russian cyclist Denis Menchov.
Heras, who was suspended by his Liberty Saguaros team when the news of the positive test was made public in November, will also be banned from competing for one of the elite Pro-Tour teams for four years.
A former team-mate of seven times Tour de France winner Lance Armstrong in the US Postal team, Heras has protested his innocence.
He first argued there must have been a laboratory mix-up and then that the testing process for EPO was flawed.
EPO stimulates the production of red blood cells, increasing oxygen-carrying capacity and therefore improving endurance.
Heras has one month in which to lodge his appeal.