Katie Ledecky confirmed her status as the queen of the Rio 2016 pool with yet another stunning victory - this time in the women's 800 metre freestyle.
The 19-year-old sensation made it five medals - four of them gold - at the Olympic Aquatics Stadium on Friday, as she destroyed the field in world record time, clocking eight minutes and 4.79 seconds to comfortably better her own landmark.
She now holds the 13 best times over the distance, and is the first teenager ever to defend a swimming Olympic title.
Ledecky followed up her victories in the 200m, 400m and 4x200m freestyle relay, as well as a rare silver in the 4x100m freestyle relay, with a typically dominant performance to match compatriot Debbie Meyer (1968) as only other woman to have won the 200, 400 and 800m freestyle events at an Olympic Games.
Trailing in her wake was Jazz Carlin of Great Britain, who finished over 11 seconds back to take silver, while Hungary's Boglarka Kapas claimed bronze.
In typical Ledecky fashion, she blew her competition out of the water, opening up a 2.59-second lead at the 200 metre mark and building on her lead every 100 meters until she touched the wall as she broke her own mark of 8:06.68 set earlier this year.
Her split at the halfway point of the race (4:01.98), would have placed her fourth in the women's 400m freestyle final on Sunday. Ledecky's final time was faster than 20 of the men's 800m freestyle splits in Friday's preliminary heats of the 1500m freestyle.
With the win and defence of her Olympic title, Ledecky's unbeaten streak moved to a perfect 15 for 15 in individual events at major international meets.