Trek-Segafredo rider André Cardoso has failed an out-of-competition test for blood booster EPO, the UCI confirmed on Tuesday.
The Portuguese rider, who was due to ride the 2017 Tour de France starting Saturday in Düsseldorf in support of Alberto Contador, was notified of an Adverse Analytical Finding of Erythropoietin (EPO) in a test sample collected in an out-of-competition control on June 18, 2017.
While the UCI won't comment further on on-going doping cases, with the rider able to request to be present at the testing of a B sample, Cardoso's Trek team released a statement saying they had suspended the rider immediately.
"It is with deep disappointment that we have just learned that our rider, André Cardoso, has tested positive for a prohibited substance," the statement read.
"In accordance with our zero tolerance policy, he has been suspended immediately.
"We hold our riders and staff to the highest ethical standards and will act and communicate accordingly as more details become available."
Cardoso, 32, only joined Trek at the start of this season having ridden for three seasons with Cannondale in its various guises.
A climber, he would have been a key helper for Contador in the mountains at the Tour having already supported he Spaniard during his build-up to the race at the Critérium du Dauphiné.
Trek have now have to draft in a veteran rider Haimar Zubeldia at short notice to replace Cardoso in their Tour line-up, with the race kicking off on Saturday with a 14km individual time trial.
The 40-year-old Basque will add 16 years of Grand Tour experience to the squad, with his best result fourth place at the Tour in 2007.
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