COPENHAGEN, DENMARK - DECEMBER 16: Aleksandr Popkov of Russia during the Men's 50m Butterfly Heats on December 16, 2017 in Copenhagen, Denmark. (Photo by Andy Astfalck/Getty Images)
COPENHAGEN, DENMARK - DECEMBER 16: Aleksandr Popkov of Russia preparing for the Men's 50m Butterfly Heats on December 16, 2017 in Copenhagen, Denmark. (Photo by Andy Astfalck/Getty Images)
