American Noah Lyles won his third world 200m title on Friday to become the first male sprinter since Usain Bolt in 2015 to seal the sprint double at the World Athletics Championships.
Lyles, who charged to 100m gold last weekend, clocked 19.52sec for the win with teenage teammate Erriyon Knighton claiming silver in 19.75sec.
Botswana's 20-year-old Letsile Tebogo claimed the bronze medal in 19.81sec to go with his silver from the 100m.
Lyles follows in the footsteps of now-retired Jamaican superstar Bolt, who completed the sprint double three times at these championships in 2009, 2013 and 2015.
He becomes just the fifth man to achieve the 100/200 metres world double after Bolt, and the American trio of Tyson Gay in 2007, Justin Gatlin in 2005 and Maurice Greene in 1999.
With a best time of 19.31sec in the 200m, Lyles is the third fastest man in history though still some way off Bolt's world record of 19.19sec set in 2009.
He had announced before the championships that he was aiming to break Bolt's record, but despite an electric start at the National Athletics Centre and a masterful home straight, that mark was never in danger.
Lyles had also vowed after his stunning victory in the 100m that he was aiming for a golden treble as a "start of a dynasty".
The US quartet earlier qualified for the 4x100m relay final on Saturday, winning their heat in a world-leading 37.68sec and offering Lyles the chance of that third gold should he be named in the final quartet.
Britain's Zharnel Hughes, who won bronze in the 100m, finished in fourth in 20.02sec, just ahead of a third American, Kenny Bednarek (20.07).
Canada's reigning Olympic champion Andre de Grasse came in sixth in 20.14, just ahead of Alexander Ogando of the Dominican Republic.
Jamaican Andrew Hudson, included after running his semi-final on Thursay with glass in his eye following a golf buggy crash en route to the track, was eighth, with Joseph Fahnbulleh in ninth spot.
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