Former Olympic champion Rebecca Adlington believes that United States youngster Katie Ledecky can break the Brit's world record.
The 16-year-old is aiming to break Adlington's record in the 800m freestyle at the World Championships in Barcelona this Saturday.
"I think she will fly on Saturday and smash my world record," Adlington told BBC Radio Five Live. "I'm looking forward to watching her at the weekend."
Ledecky has won gold in the 1500m and the 400m.