In damp conditions, Kejelcha, who also owns the world record for the indoor mile, established in Boston in 2019, finished in 57 minutes and 30 seconds in the Spanish capital.
The 27-year-old’s time was one second faster than the mark set three years ago in Lisbon by Ugandan Jacob Kiplimo.
With a time of 63:04, Kenyan Agnes Ngetich won the women’s race and rose to second in the world’s all-time rankings.
After settling in behind the pacemakers from the beginning of his sixth half marathon, Kejelcha made his move around the three-kilometer mark and eventually overtook Kenyans Daniel Mateiko and Isaia Kipkoech to win.
Earlier this year, Kejelcha, a two-time world indoor 3000m champion, only managed to place sixth in the 10,000m final at the Olympics in Paris.
