CHICAGO, Ill. (WTVO) — The fastest man over 26 miles was crowned in Chicago on Sunday as Kenyan runner Kelvin Kiptum set a new world record at the 2023 Chicago Marathon.

Kiptum, 23, set the world-record marathon time at 2:00:35 (two hours, 35 seconds), breaking the previous record of 2:01:39 (two hours, one minute and 39 seconds) set by fellow Kenyan Eliud Kipchoge at the Berlin Marathon on September 25, 2022.

The young Kiptum has burst onto the long-distance running scene. In 2022, he ran the fastest ever marathon debut at the 2022 Valencia Marathon and became only the third person in history to complete the race in under two hours and two minutes with a time of 2:01:53.

The 23-year-old followed up his debut performance with a win at the 2023 London Marathon in April. Sunday’s marathon marked just his third official performance.

“I knew I was coming for a course record, but a world record — I am so happy,” Kiptum said, 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.”

Kiptum’s time is unofficial until it is ratified by World Athletics.