RIO DE JANEIRO — Michael Johnson knows a thing or two about international competition, and he surely knows a great deal about the Olympics.
Johnson was part of a gold-medal 4x100 relay team that set a world record in the 1992 Olympics, then became a legend in the 1996 Olympics, when he set a world record in the 200-meter sprint, and followed that with an Olympic record in the 400-meter. He added a gold medal in the 400 in Sydney in 2000.
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He knows something about doping cheats, too.