The women emulated the men on Wednesday when American Sydney McLaughlin smashed her own world record in the 400 metre hurdles for gold at the Tokyo Olympics.
Fellow American Dalilah Muhammad led for most of the race, but McLaughlin sped ahead at the final hurdle to take gold in 51.46 seconds.
World champion and 2016 gold medallist Muhammad also stayed well below McLaughlin’s previous record of 51.90 from earlier in the year, clocking 51.58. Dutch ace Femke Bol earned bronze in a European record 52.03.
The fast times came 24 hours after Norway’s Karsten Warholm had also obliterated his world record in the men’s final, lowering it by .76 of a second to 45.94 seconds on the fast Tokyo track.
“I’m absolutely delighted. What a great race. I’m just grateful to be out here celebrating that extraordinary race and representing my country,” McLaughlin said.
“I saw Dalilah ahead of me with one to go. I just thought ‘Run your race’,” she said.
“The race doesn’t really start till hurdle seven. I just wanted to go out there and give it everything I had. It’s just about trusting your training, trusting your coach, and that will get your all the way round the track.”
Muhammad said: “This means everything to me at this moment.
“It shows the hard work, that I’ve been able to accomplish it, how proud I am of this moment and putting things into perspective of the career that I’ve had. To be 31 and running at your very, very best is absolutely amazing.”
Earlier, German top favourite Johannes Vetter escaped a huge scare in javelin qualifying, making the final only in bis third and final attempt of 85.64m.
But Rio 2016 silver medallist Julius Yego of Kenya, and bronze medallist Keshorn Walcott of Trinidad and Tobago both failed to make the final.
The multi events also go under way, with Canada’s Damian Warner top of the decathlon after three events with 2,966 points in his bid for a first big title, starting with an impressive 10.12m in the 100m.
“It was a great start, a start I was looking for,” he said. “It is kind of on par with what I had earlier this year, when I had my lifetime best performance (of 8,995 points).
“I just have to keep building on this, and keep executing. We have high jump and 400m later today. I have to finish strong, and come out tomorrow with the same kind of energy.”
French world record holder Kevin Mayer was fourth after the 100m, long jump and shot put with 2,662 points, and German world champion Niklas Kaul 18th after a modest start on 2,474 but his strongest events yet to come.
Belgian star Nafissatou Thiam topped the women’s heptathlon with 2,176 points from the 100m hurdles and high jump, just ahead of an American Erica Bougard (2,157) and world champion Katarina Johnson-Thompson (2,138).