Allyson Felix participant in 2004 Summer Olympics
Professional
Early career
At the 2003 U.S. national championships, the seventeen-year-old phenomenon finished second in the 200 meters sprint with a time of 22.59 seconds, earning her spot to the 2003 Paris World Championships. In the quarter-finals of the 200 meters in Paris, Felix finished sixth in 23.33 seconds.
At the age of 18, Felix earned an Olympic silver medal in the 200 meters at the 2004 Summer Olympics in Athens, behind Veronica Campbell of Jamaica; in doing so, she set a world junior record over 200 meters with her time of 22.18 seconds. After leaving Athens, Felix and her coach Pat Connolly, who also guided the 1984 Olympic 100 meters champion Evelyn Ashford, parted ways as Connolly moved back to Virginia and Felix cited difficulties training alone. The young sprinter then sought the tutelage of controversial sprint coach Bob Kersee, whom she would train under for the next 18 years.Nineteen-year-old Felix became the youngest world champion ever in the 200 meters at the 2005 Helsinki World Championships and then successfully defended her world title in Osaka two years later. At the 2007 Osaka World Championships, Felix caught Jamaican rival, Veronica Campbell, on the bend and surged down the straightaway to finish in 21.81 seconds, dipping under the 22-second barrier for the first time in her career. After the final, Felix stated in the post-race interview: "I feel so good. I am so excited. I have been waiting for so long to run such a time, to run under 22 seconds. It has not been an easy road, but finally, I managed." At that time, she addressed her future, saying, "My next goal is not the world record, but gold in Beijing. I want to take it step-by-step. I might consider doing both – the 200 and the 400 meters – there." Days later, after partaking in the winning U.S. 4 × 100 meters relay and also the 4 × 400 meters relay, in which she unofficially split 48.01 seconds on the second leg,  Felix became only the second female athlete, after Marita Koch in 1983, to win three gold medals at a single IAAF World Championships in Athletics.
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