The athletics world has been left stunned after a dramatic 48 hours in which the women's 10,000 metres world record was broken twice, by two different competitors.
Dutch runner Sifan Hassan had set a new world benchmark in the 10,000m after running it in 29 minutes 06.82 seconds to slice almost 10 seconds off the record set by Almaz Ayana at the 2016 Olympics.
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However, the record lasted just two days after Ethiopia's Letesenbet Gidey has smashed her Dutch rival's time on the same track in The Netherlands.
Gidey shaved five seconds off Hassan's mark to finish in 29:01.03, more than a minute ahead of runner-up Tsigie Gebreselama.
The Ethiopian now holds two world records after last year setting a new benchmark in the 5,000m event.
Her latest remarkable feat has left athletics fans in a frenzy on social media, with many relishing the prospect of Gidey and Hassan going toe-to-toe at the upcoming Tokyo Olympics.
'Perfect preparation' for Olympics
Until Ayana's gold medal performance in Rio no runner had come anywhere near the controversial 1993 record of 29:31.78 set by China's Wang Junixa - where shoe technology featuring carbon plates and thick foam insoles enabled athletes to rip up the record books.
"I expected to run a world record," the 23-year-old Gidey, who was aided by Wavelight Technology and becomes the first woman to hold both the 5,000m and 10,000m world records since Norway's Ingrid Kristiansen from 1986-1993.
"What a special night, I am so proud that after the 5,000 metres world record I am now the 10,000 metres world record holder as well.
"In this Olympic year it is the perfect preparation (for next month's Tokyo Games)."
Meanwhile, two British ultra-runners smashed the world record by covering more than 330 miles (530km) of a 4.2-mile (6.8km) course in Suffolk, England.
John Stocker took the ultimate honours as the last man standing more than three days after the race started.
The 41-year-old and Matt Blackburn, 35, were among the field of 123 for the event.
Ultra runners and mesmerised observers around the world became gripped online by the astonishing performances in a small-scale event as neither man was prepared to stop.
The world record came and went before, finally, Blackburn "rang the bell" to signal that he could go on no more and slumped into his chair having covered 333.3 miles (536.4km).
Stocker, however, still had to complete his 81st lap or, by the harsh rules of Back Yard events, there would be "no winner."
He duly did, as his 81st and final lap took him to an astonishing final distance of 337.5 miles (543km).
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