After winning the Olympic 10,000m title in Rio de Janeiro with a runaway world record, Ethiopian Almaz Ayana made sure her margin was even bigger at the worlds - make that three times as big.
Ayana won in 30m 16.32s, 46.37s ahead of Ethiopian teammate Tirunesh Dibaba. In track terms, that is more than 300m in a 10,000m race. Agnes Tirop of Kenya took bronze.
Ayana came into the championships swirled in mystery. She had no official time for the 10,000m this season and had been hampered by injury.
"I have been sick this year and didn't expect it," Ayana said. "This was my first race of 2017."
It was a long, lonely road around the 25 laps of the London Stadium for New Zealand runner Camille Buscomb, who finished 30th in 33m 07.53s.
Buscomb was towards the back of the field from the start. From halfway, she was unable to maintain contact with a group of runners and spent the remainder of the race battling her way on her own.
Buscomb acknowledged that she didn't feel very good and doesn't know what the problem is.
"I'm just not quite right, whether it's because I've been doing a lot of training. It's real unfortunate," said Buscomb. "Maybe I'm a bit fried, I haven't been feeling my best for a while but maybe I've just got to keep pushing and keep training and I'll be right. But I just felt horrible the whole way. It's a long grind when every step is pretty hard, but I didn't want to pull out."
In the long jump, Luvo Manyonga of South Africa took gold with a leap of 8.48m, holding off Jarrion Lawson of the United States by 4cm and going one better than his silver at last year's Olympics. Ruswahl Samaai, also from South Africa, took bronze with a jump of 8.32m.
Andrius Gudzius of Lithuania won his first major discus title. He threw 69.21m, holding off favourite Daniel Stahl of Sweden by just 2cm.