After all of these years, all of those lonely laps when the clock seemed to be the only worthy adversary, Katie Ledecky finally has some company.
Ariarne Titmus wasn't able to beat the American star in the 400m freestyle final at the Pan Pacs meet in Tokyo but as far as the 2020 Olympics are concerned, it's offically game on between the pair.
Big improver: Ariarne Titmus appears dejected after finishing second in the women's 400m freestyle final.
Ledecky, the Olympic, world and Pan Pacs champion, has never lost an international 400m and didn't go under on Saturday night at the Tatsumi International Swimming Centre, taking out the race in 3:58.50s.
But it was the rise and rise of Australia's Titmus, still just a 17-year-old schoolgirl, that set the scene for an epic showdown in the nearby Olympic pool in two years.