After anti-doping officers from Spain's Commission for the Fight against Doping in Sports (CELAD) showed up to perform random controls on riders of the amateur Interclub Vinalopó in Villena, Spain on Saturday and only 52 of the 182 starters came through the finish line.
Usually about half of the peloton - a mix of junior, masters and amateur racers - finishes the race in Villena, according to Ciclo21, and less than a third of the racers completing the route in Valencia led to suspicions that riders were avoiding the random doping controls.
A four-rider breakaway got away in the hilly 85-kilometre race which was live-streamed on YouTube, with two riders staying away. Andrea Ripolli, 26, out-sprinted Jose Manuel Diaz, 42 to take the win.
Álvaro Marzà, who placed eighth from the chasing group, called the mass drop-out 'a fucking joke' in a post on Instagram, as reported by Ciclo21.com.
"Anti-doping control in Villena = punctures and withdrawals. It is not a mathematical formula, it is pure reality. Let's see if measures are taken because this is a fucking joke. By the way, I have passed control!," Marzà wrote.
One anonymous racer interviewed by Ciclo21 said, "We all know who is and who is not [doping].
"We are fed up with these exhibitions and that when there are controls, curiously the same as always, they do not finish the races to avoid the control, but of course without evidence we cannot accuse, but everything is very evident.
"Last year one of them went off the road and went through the bush to avoid entering the finish line and prevent the anti-doping agents from being able to control him. It's that sad..."
Race organisers issued a statement saying they were, "committed to the fight against doping and believe it is essential to maintain the integrity of the sport and protect the health of cyclists".
"Doping is a trap that gives cyclists who use it an unfair advantage over those who compete fairly. Not only is it disrespectful to the sport and its values, but it can also have serious consequences for the health of cyclists who dope."
The organisers said they follow UCI rules which allow for all participants to be subject to random drug testing.
"We want to send a clear message to all cycling participants and fans: doping has no place in our sport. We support cyclists who compete fairly and honestly and are determined to protect the integrity of cycling."
Spain is not the only country with an amateur doping problem. In the United States, a group in Florida raised funds to bring doping controllers to their races after the Lance Armstrong scandal.
USA Cycling soon got on board with their "RaceClean" programme in 2013 after feedback from members.
