Zharnel Hughes broke the 30-year British 200m record by clocking 19.73 seconds in front of a sell-out 50,000 crowd at the London Diamond League.
The 28-year-old took 0.21 secs off the previous mark of 19.94, set by John Regis at the 1993 World Championships.
The record time saw Hughes take third, with American world 200m champion Noah Lyles winning in 19.47 secs.
It is the second long-standing national mark Hughes has broken this season, having smashed the 100m record in June.
Hughes, who ran 9.83 secs in New York to better Linford Christie's time in 1993, previously ran 19.77 with an illegal wind speed to claim the UK 200m title in Manchester earlier this month.
Compatriot Dina Asher-Smith ran a 100m season's best of 10.85 secs to place second behind Marie-Josee Ta Lou of the Ivory Coast.
That put her ahead of Jamaica's world 200m champion Shericka Jackson, with Britain's Daryll Neita taking fourth in 10.96 secs.
However, Keely Hodgkinson withdrew before the women's 800m as a precaution because she was feeling unwell.
The 21-year-old Briton had been excited to compete at London Stadium for the first time but will now focus her attention on next month's World Championships in Budapest and the chance to achieve the gold she missed out on by 0.08 seconds last year.
Sunday's competition, the first major athletics meet to be held at London Stadium since 2019, represented one of the final opportunities for some of the sport's biggest names to fine-tune their preparations for the worlds, which start on 19 August.
Hughes delivers on brilliant day of athletics
Hughes, 28, predicted his 100m British record, writing it down in his notebook on the morning of the race.
While he would not commit to targeting the 200m mark on Sunday - despite Lyles' insistence during the pre-event news conference that the time was within reach - a captivated home crowd celebrated with the Briton as his time appeared on the big screen.
Hughes, born in Anguilla and living in Jamaica, uses a vision board at home to map out his goals.
He recently told BBC Sport he has another 100m time written down, which he hopes to achieve at the World Championships, and this performance will leave him full of confidence as his full attention turns to Budapest.
Lyles, who will target an ambitious trio of world golds in the 100m, 200m and 4x100m relay next month, showed he remains the man to beat over the longer sprint as he held off Botswana's Letsile Tebogo.
Asher-Smith continues to improve but Hodgkinson misses out
With less than four weeks to go until the World Championships, Asher-Smith continues to look sharper as the season progresses.
The 27-year-old 2019 world 200m champion followed up the 200m season-best she posted in Monaco on Friday with her best 100m performance of 2023 in a high quality field.
Jackson has recorded the fastest time in the world this year but was never involved at the head of the race as Ta Lou took victory, with Asher-Smith roared on all the way to her latest promising time.
Neita can also have few complaints after improving to 10.96 this season, finishing 0.02 secs behind Jackson.
Hodgkinson's absence was an undoubted loss, with the in-form Olympic and world silver medallist expected to produce the grand finale to proceedings.
However, in her absence, Jemma Reekie delivered a stunning run - setting a meeting record of one minute 57.30 secs to hold off Jamaica's Natoya Goule-Toppin.
Van Niekerk stars as world's best descend on London
Wayde van Niekerk continues to try to rediscover his best form after sustaining a serious knee injury in 2017, just months after retaining his world title at the World Championships in London six years ago.
Returning to that venue, South Africa's world record holder ran 44.36 secs to take victory in a race in which Matthew Hudson-Smith finished fourth in a season-best 44.72 secs before being assisted off the track in a wheelchair.
Elsewhere, the Netherlands' Femke Bol dominated the women's 400m hurdles field, winning by more than two seconds as she set an improved world-leading time of 51.45 seconds.
American Quanesha Burks jumped a personal best 6.98m to win the women's long jump, in which European indoor champion Jazmin Sawyers (6.67m) and former world heptathlon champion Katarina Johnson-Thompson (6.60m) finished fourth and fifth respectively.
American Yared Nuguse took victory ahead of Norway's Narve Gilje Nordas in three minutes 30.44 secs in the men's 1500m, with the pair followed by a trio of British athletes.
Neil Gourley (3:30.60), Elliot Giles (3:30.92) and Matthew Stonier (3:31.30) all ran personal bests.
London Marathon winner Sifan Hassan was made to settle for third in a women's 5,000m won by world champion Gudaf Tsegay in 14:12.29 - despite the Olympic champion running a European record time of 14:13.42.
Meanwhile, Britain's Aimee Pratt took third with a season-best time of 9:16.10 in the women's 3,000m steeplechase as Jackline Chepkoech stormed to victory in the women's 3,000m steeplechase in a new world lead of 8:57.36.
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