Kelvin Kiptum sets new unofficial men's marathon world record at Chicago Marathon

CHICAGO -- The men's marathon world record time was shattered Sunday at the 2023 Bank of America Chicago Marathon.

Kenya's Kelvin Kiptum broke the men's marathon world record, becoming the first person to record a time faster than 2:01:00, crossing the line in 2:00:35.

NOTE: The video in the player above is from a previous report. Pictured above is Kiptum after his win at the London Marathon in April.

Running just the third competitive marathon of his career, the 23-year-old shaved 34 seconds off the previous world record which had belonged to his compatriot Eliud Kipchoge, though it is still subject to the usual ratification procedure, according to World Athletics.

He completed the race almost three and a half minutes ahead of anyone else; Kenya's Benson Kipruto finishing in second and Belgium's Bashi Abdi in third.

"I knew I was coming for a course record, but a world record - I am so happy," Kiptum said afterwards, according to World Athletics. "A world record was not on my mind today, but I knew one day I would be a world record-holder."

READ MORE | Thousands of runners participate in 2023 Bank of America Chicago Marathon

Despite the magnitude of his achievement fast approaching, Kiptum still seemed to be running within his limits as he sprinted the towards the finishing line, celebrating wildly before picking up a Kenyan flag and embarking on a victory lap.

He had remained outside world record pace at the halfway point with a time of 1:00:48 but accelerated 10 kilometers from the finish to seal his place in the history books.

Such a result has long seemed possible for Kiptum, who completed the fastest ever marathon debut race last December and set a course record in London in April with a time just 16 seconds outside of Kipchoge's then world record.

Meanwhile, Sifan Hassan broke the women's course record in Chicago with a time of 2:13:38, the second-fastest ever race, as she made her US marathon debut.

More records tumbled in the wheelchair races too as Switzerland's Marcel Hug and Catherine Debrunner set course records in the men's and women's races respectively.

There were 49,000 runners from all 50 states and more than 100 countries who participated in the race, organizers said. The marathon route runs through 29 Chicago neighborhoods for the 26.2-mile course.

Race organizers expected more than 1 million spectators to line city streets along the marathon route.

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ABC7 Chicago contributed to this report.