He did not take up athletics until after he left school, but was spotted by Paul Ereng and won the African Junior Championships in 2001 despite falling.

[3] Kemboi became African Junior Champion in 2001 and then in 2002, he finished second at the Commonwealth Games behind compatriot Stephen Cherono.

The same year Kemboi was originally fourth at the African Championships in Athletics, but was later awarded bronze after the winner Moroccan Brahim Boulami received a doping suspension.

The race went very much according to form, with the three Kenyans Kemboi, Brimin Kipruto and Paul Kipsiele Koech pushing the pace from the second lap and soon leaving the rest of the field behind and Kemboi winning a gold medal 0.3 seconds ahead of Kipruto in a Kenyan sweep.

Kemboi represented Kenya at the 2008 Beijing Olympics but managed only seventh – his worst performance on the global stage.

This was his seventh World medal, setting a record for any athlete, which would subsequently be surpassed by Chinese shot putter Gong Lijao in 2023.

[11] An investigation into the incident was instigated when the French Olympic team complained that the runner had stepped out of the track after his final water jump during the race.

[13] His participation in the 2012 Olympics was initially put in doubt when he was charged with assault in June 2012, after a woman claimed he stabbed her after she refused his sexual advances.