( CNN ) -- Missy Franklin rewrote swimming 's record books with a sixth gold medal at the world championships in Barcelona Sunday . The 18-year-old American swam the backstroke leg as the U.S. won the 4x100m medley relay on the final day of competition . Franklin surpasses Tracy Caulkins of the U.S. and Australia 's Libby Trickett , who both won five golds at a single world championship in the women 's competition . Only the great Michael Phelps has won more events at the championship , taking seven golds in 2007 in Melbourne . Swimming the backstroke leg , Franklin gave her team a healthy lead with Jessica Hardy , Dana Vollmer and Megan Romano finishing off the job as the U.S. won by nearly two seconds from Australia with Russia third . Dubbed `` Wonder Woman '' by an Australian rival earlier in the championships , Franklin has lived up to the tag with other golds coming in the 4x100m freestyle relay , 100m backstroke , 200m freestyle , 4x200m freestyle relay , 200m backstroke . Fourth in the 100m freestyle final and withdrawal after qualifying for the semifinals of the 50m backstroke have been the only blemishes on her record in Spain . She will now head to the University of California in Berkeley to continue her studies , but more importantly for now , prepare for the 2016 Olympics in Rio . Franklin won four golds at the 2012 London Games and will be hotly tipped to improve that tally four years later , given her current dominance . The success of the women 's medley relay team came after their male counterparts were disqualified for an illegal handover after finishing first . France were awarded the gold . The other dominant swimmer of the championships , China 's Sun Yang , won the men 's 1500m freestyle gold to complete a hat-trick of long distance events , having won the 400 and 800m titles . The 21-year-old , who burst to prominence at the London Games . beat Canada 's Ryan Cochrane with Italy 's Gregorio Paltrinieri in third . Watch : Teen Olympian inspires community . France won two golds on the final day , with Camille Lacourt taking the men 's 50m backstroke before their men 's medley team took advantage of the mistake by the U.S. team . Yulia Efimova of Russia turned the tables on 16-year-old Lithuanian Ruta Meilutyte in the women 's 50m breaststroke final to win her second gold medal . Meilutye , who took the 100m title , broke Efimova 's world record for the 50m in the semifinals , but lost out to her by just 0.07 seconds in the battle for gold . Efimova also won the 200m title .
Missy Franklin claims record sixth gold at swimming world champs . Franklin part of victorious U.S. team in 4x100 medley relay . China 's Sun Yang wins third gold in men 's distance events . Ruta Meilutyte beaten in women 's 50m breaststroke final .