Felix eventually chose the 400 meters and later triumphed in the event final with a personal best of 49.26 seconds. She dominated the race from beginning to end, making up the stagger from the start of the gun and never relinquishing her lead to claim the 400 meters title. In doing so, Felix became the first woman to win world titles in the 200 meters and the 400 meters. Additionally, she has now won the most world championship gold medals, and most world champion overall medals, out of any American track and field athlete. Later in the championships, she earned silver medals in both the 4 × 100 meters relay and 4 × 400 meters relay. In the latter race, Felix received the baton with a huge deficit to the leading Jamaican team, prompting her to sprint a historic split time of 47.72 seconds to regain the lead for the American women before the final handoff. Running the final leg, Francena McCorory failed to hold onto the lead and was overtaken by Novlene Williams-Mills in the final meters.