Double Mexican national champion Luis Villalobos has been banned for four years for doping.
Cycling’s governing body UCI said on Wednesday that a tribunal had found the presence of a growth hormone-releasing substance called GHRP-6 in a sample provided by the rider in 2019 when he was with US team Aevolo.
The substance is on the World Anti-Doping Agency’s prohibited list and is used to speed up weight loss and increase muscle mass.
Tour de France
Tour de France Yellow jersey guide and predictions: Three but not so easy for Pogacar?
The 23-year-old had been provisionally suspended in May last year from his new team EF Pro Cycling when UCI wrote to the team about a potential doping violation.
"If we'd have known, we would not have signed Luis,” the team’s CEO Jonathan Vaughters said.
“The burden of this is on the UCI because there is no internal testing program that has access to the level of equipment needed to screen for GHRP-6."

Luis Villalobos bei der Polen-Rundfahrt 2019

Image credit: Getty Images

Villalobos won the national time trial in Mexico in 2018 and 2019.
He was named Best Young Rider at the Tour of Utah, where he also placed fourth in a stage and then eighth overall.
During his spell with EF Pro Cycling, the Mexican rider competed at the Tour of Poland, Tour of Britain, EuroEyes Cyclassics Hamburg and Bretagne Classic in 2019.
Tour de France
Contador rates Tour chances for Thomas, Yates, not ruling out Cav return
Tour de France
‘We sleep like babies, we work like horses’ - Bahrain Victorious boss protests innocence