Shanghai: Italy`s Federica Pellegrini retained her women`s 200 metres freestyle world title, completing the 200-400 double at the championships for the second time.
Pellegrini, who also won both freestyle titles at the 2009 worlds in Rome, clocked one minute, 55.58 seconds to win gold, just ahead of Australia`s Kylie Palmer who took silver in 1:56.04. Camille Muffat of France secured bronze in 1:56.10.
Italian Pellegrini became the first woman to complete the 200-400 double at a world championships for a second time.
The double had been completed just three times previously, Shirley Babashoff (United States) did it in 1975; Heike Friedrich of East Germany achieved it in 1986, while France`s Laure Manaudou did it in 2007.
"I`m very happy and very proud of the gold medal," Pellegrini told reporters. "My coach (Philippe Lucas) is great and very important for me to win the gold medal and I am improving (and) my goal is the London Olympics."
Pellegrini achieved her second double the hard way, falling well off the pace to be in fifth in the first 100 metres, before she surged in the third lap and turned for home in third place where she quickly overtook Allison Schmitt and fastest qualifer Femke Heemskerk.
Palmer, who had turned for home in seventh place, produced a strong finish to haul in virtually the rest of the field but it was not enough to pass Pellegrini.
"I am so happy with it. I am almost crying, because it is so tough," Palemr said. "I did not know I fell so far behind during the race (but) I am pretty excited."