Former world boxing champion Erik Morales of Mexico tested positive in two random samples taken ahead of his loss last October to Danny Garcia, the US Anti-Doping Agency (USADA) said Friday.
Morales has received a two-year ban as a result of the violation after refusing the chance to challenge the findings in an arbitration process.
The 36-year-old pro fighter tested positive for the banned anabolic agent Clenbuterol in out-of-competition urine tests October 3 and 10 in Mexico, although it proved to be little help in the ring on fight night.
Unbeaten American Garcia knocked out Morales in the fourth round on October 20 in New York to keep the World Boxing Association and World Boxing Council light-welterweight titles.
Garcia defends the crowns against Zab Judah next month.
Morales, 52-9 with 36 knockouts, has lost three of his past four fights, including a showdown with Garcia last month in which he failed to make the weight limit and lost a unanimous 12-round decision.
Pro boxing does not have a World Anti-Doping Agency-accredited program, but many boxers and promoters pay USADA to conduct more comprehensive doping tests than those mandated by state boxing commissioners before certain bouts.
USADA's program includes random, no-notice out-of-competition tests of blood and urine with all analysis completed before the fight and requires both fighters to agree to abide by USADA's anti-doping rules.