Usain Bolt blasted Tyson Gay's use of steroids, as well as the authorities that banned him for just a year over his drug use, claiming his sprint rival should have been kicked out of the sport.
Gay, an American sprinter, is the second-fastest man of all time behind Jamaica's Bolt. He received a yearlong ban in May 2014, the backdating of which saw him stripped of his 100-meter silver medal from the 2012 Olympic Games.
Gay returned to the track last year but has yet to race against Bolt, a six-time Olympic gold medal winner.
Bolt has revealed his newfound disdain for Gay — a rival he claims to have respected.
"I was really upset about that," Bolt said in an interview with Runners World, released by The London Times. "He got a year just because he talked to the authorities about how it was done and who helped him. That sends the wrong message: 'If you do it and get caught, just tell us all you know and we'll lower your ban'.
"It's the stupidest thing I've ever heard. The message should be: 'If you cheat you're going to be kicked out of the sport'. It really bothers me.
"I'm not worried about him beating me, I think it's because I respected him so much over the years. He was a competitor, kept me on my toes and he pushed me to always do my best," Bolt added. "Then to find out that he was on drugs — it's a bit like I think parents must feel when they have a kid who does something bad and lets them down. I feel like he let me down and he let the sport down."