"Fairly sure Katie Ledecky isn't human" - Serena Williams' ex-coach congratulates American swimmer on breaking Michael Phelps' record title haul

Former Serena Williams coach Rennae Stubbs lavished praise on Katie Ledecky after she set a new record for the most number of world titles by any swimmer.

The 26-year-old competed at the World Aquatics Championships in Fukuoka, Japan, and won the 800m freestyle event for the sixth successive edition. She finished ahead of the likes Li Bingjie (2nd) and Ariarne Titmus (3rd).

This is Ledecky's 16th gold at the world championships, which saw her surpass the legendary Michael Phelps for the most number of world titles by any swimmer, male or female.

The American star was congratulated by Serena Williams' former coach Rennae Stubbs, who joked that she isn't a human.

"Fairly certain @katieledecky isn’t human! Wow! What a swim. Most world titles EVER, by ANY swimmer! CONGRATULATIONS," Stubbs tweeted.

Apart from her gold in the 800m freestyle event, Ledecky also won the silver medal in the 400m freestyle tournament at the World Aquatics Championships. In that event, she finished behind Ariarne Titmus, who set a new world record.

She also earned another silver in the 4x200m freestyle competition, with the United States losing to Australia.

Rennae Stubbs hailed Noma Noha Akugue for reaching the final of the Hamburg European Open on WTA Tour debut

Rennae Stubbs while coaching Serena Williams during the 2022 US Open

Rennae Stubbs heaped praise on German teenager Noma Noha Akugue after she reached the final at the Hamburg European Open, which was her very first tournament on the WTA Tour.

The 19-year-old received a wildcard for the WTA 250 event and booked her place in the title clash following wins over Laura Pigossi, Storm Hunter, Martina Trevisan, and Daria Shnaider.

Stubbs congratulated Akugue on her run and claimed that she had a good future ahead.

"Huge week for Noma Noha Akugue!!!! Unbelievable!!! This kid is here to stay. Fantastic attitude, great power game, and her composure is fantastic," the Aussie coach tweeted.

Rennae Stubbs is a former doubles World No. 1 who won a total of six Grand Slams, four in women's doubles and two in mixed doubles. All in all, she claimed 60 WTA doubles titles.

Stubbs retired from tennis in 2011 and currently works as an analyst. She coached Serena Williams during the 2022 US Open, which turned out to be the last tournament of her illustrious career.