Ignacio Maldonado, from Uruguay, tested positive in a control carried out after the first stage of January's Vuelta Ciclista a la Provincia de San Juan in Argentina.
Maldonado was competing at the January 21-28 UCI 2.1 race with the Uruguay National Team. He tested positive for the EPO variant known as CERA in a sample taken after stage 1 on January 21 and is listed on the UCI's provisional suspension file.
Maldonado finished 27th in the opening stage of the Vuelta a San Juan, his best placing during the seven-day race, and he went on to finish 86th in the final general classification.
Maldonado's top results previous to this year were a third place at the Uruguayan National Championships in 2017, and he won a stage of the Vuelta Ciclista del Uruguay in 2010.
In February, a post from the official Twitter account for the Vuelta a San Juan claimed that there was a positive anti-doping result from the January race and that more information would follow. However, the post was quickly deleted and the organisation later said that a hacked Twitter account was responsible for a message that went out over social media.