The superstars showed up big time on day six at the IAAF World Championships in Beijing. American Allyson Felix was dominant from start to finish in the 400 meters, capturing gold.

Usain Bolt also captured the headlines completing yet another 100/200 meter double, defeating American Justin Gatlin by .19 seconds. The victory was Bolt's third 100-200 double in his career at the World Championships and his 10th World Championship gold of all-time.

Felix dominates from start to finish

Felix was the heavy favorite in the race coming in. She was the only woman to go under 50 in the semifinal heats. However, she still had some serious competition from Great Britain's Christine Ohuruogu, Jamaica's Shericka Jackson, and the Bahamas own Shaunae Miller.

The American flew out quickly out of the gates unlike the US Trials where she eased early on before picking up the pace. In the first 200 alone, she already had set herself apart from her three main competitors, storming past Ohuruogu quickly.

In the homestrech, the Brit looked spent as Felix stormed her way to the United States' third gold of the World Championships with a world leading time of 49.26. Jackson and Miller finished with silver and bronze respectively.

Bolt with yet another sweep

Much like the 100 meter race, this one was shaping up to be a matchup for gold between Bolt and Gatlin. Both men were the only two to go under 20 seconds in their respective (and all) semifinal heats.

When the gun sounded, Bolt was out quickly with Zharnel Hughes of Great Britain. The Jamaican had the strong 100 meter start and with Gatlin still trailing, there was not a chance Bolt would relinquish the lead. It was Bolt once again in dominating fashion. The Jamaican captured yet another 100/200 double and won with a world leading time of 19.55.

Gatlin finished runner-up once again, this time getting blown out though, with a time of 19.74. Anaso Jobodwana of South Africa finished third after time was sent to the thousandth of a second mark after tying with Alonso Edward. This is Bolt's fifth 100/200 sweep all-time (missed out in 2011 due to a false start in the 100). Other than that though, he's been flawless in the Olympics and World Championships. He looks to complete the "Holy Grail" of sprinting gold by looking to anchor the Jamaican 4x100 relay team to a potential gold on Saturday.

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