Yomif Kejelcha obliterated the old record, which was yet to be ratified. (Instagram: @maratondebuenosaires)
Yomif Kejelcha has set a half-marathon world record with a time of 56 minutes, 51 seconds.
That time is equivalent to running four consecutive parkruns in a time of 13 minutes and 28 seconds each.
Kejelcha's mark is subject to ratification by World Athletics.
Yomif Kejelcha has smashed the half-marathon world record, running a staggering 56 minutes and 51 seconds at the Media Maratón Ciudad de Buenos Aires in Argentina on Sunday.
The Ethiopian shaved 29 seconds off the previous mark of 57:20, which had been set by Uganda's Jacob Kiplimo in Lisbon in March.
Kejelcha's time and that of the record he just beat are still subject to ratification by World Athletics.
The Media Maratón Ciudad de Buenos Aires is a World Athletics Label road race and took place under favourable conditions of 6 degrees Celsius and with a slight breeze.
As ever, the super shoe gets plenty of post-race love from Yomif Kejelcha. (Instagram: @maratondebuenosaires)
Tadese Worku (59:20) and Bereket Nega (1:00:20) of Ethiopia completed the podium.
"I'm over the moon," Kejelcha told World Athletics.
"I'm super happy and right now I don't feel any tiredness. The travel from Ethiopia was too long and I was tired the first days here, but later I felt better and today I was full of beans.
"I had planned to run conservatively over the early stages, but I felt good and decided to give it my all.
"This time is unbelievable. I can't describe it with words.
"I now hope to try the Argentinian meat, which has a very good reputation, and this afternoon I have been invited to watch the River Plate-Vélez football match. I'm very grateful."