MANILA, Philippines – Juan Manuel Marquez blames boxing coach Freddie Roach for starting rumors of his alleged use of performance enhancing drugs (PED).

Marquez, who bulked up for his fourth clash with Manny Pacquiao, maintained that he never used banned substances to gain muscle mass.

"For me it was unbelievable that on the social networks it was being said that I was taking banned substances. I'm a clean fighter with 20 years of a trouble-free run. Freddie Roach told me that he would to kiss my ass if my body was clean and the drug test results showed that there was nothing there,” the boxer said in a Boxing Scene report. 

Prior his fighter’s defeat to Marquez, Roach raised suspicions on Marquez’s ability to gain muscle size in a short time.

Further fueling the speculation was Marquez’s association with Angel Hernandez, who admitted to distributing PEDs to Olympic athletes in the past.

But the Mexican asserted that his bulked-up physique was a result of hard work.

“My physical changes were the direct result of four-and-a-half months of tough training sessions. The formula is work, work and work," Marquez said.