Kenya's former Olympic and world 1500m champion Asbel Kiprop has vowed to fight on to clear his name after being handed a four-year suspension on Saturday for using the banned blood-booster EPO.
The 29-year-old failed an out of competition test in November 2017 and was provisionally suspended in 2018.
On Saturday, the Athletics Integrity Unit (AIU) upheld that ban, concluding that the case had been "convincingly made out" despite an "a la carte menu of reasons why the charges should be dismissed" from Kiprop's representative.
After the verdict, Kiprop continued to maintain his innocence.
"The decision is not only a blow to me, but it is not good for the sport of athletics," Kiprop told AFP.
"I have been insisting that I did not dope," he said.
"I will continue to maintain my innocence, even if this decision now means I will not be eligible to run again for the next four years.
"It's sad that the world will believe that I am guilty of taking the performance-enhancing drugs and yet I have been at the forefront of fighting doping in the sport."
It went on to state that at the hearing his representative, Katwa Kigen, presented an "a la carte menu of reasons why the charges should be dismissed."
The AIU statement added that while Kigen presented his arguments with "tenacity and charm" the International Association of Athletics Federations (IAAF) representative Ross Wenzel had argued that "none of the various reasons proposed...when subject to strict scrutiny had any plausibility."