Michael Sohn/Associated Press

Yesterday, Katie Ledecky won the 1500 meter freestyle world championship by 19 seconds. It was her 12th gold medal at worlds, a record for women swimmers, breaking a tie with Missy Franklin.

Fifty minutes later, Ledecky won her semifinal heat in the 200 meter free to advance to today’s final. She’d already won three gold medals at this year’s world championships. With three races to go, she had a chance to tie Franklin for the women’s record for most golds at a single worlds.

Today, she lost—the first time she’s ever finished second in a race at the world championships. She was 12-for-12 previously.

Italy’s Federica Pellegrini ended Ledecky’s winning streak with a 1:54.73 time, ahead of Ledecky’s 1:55.18. Australia’s Emma McKeon tied Ledecky for the silver medal.