Nicknamed "Mr. YouTube" because he learned how to throw by watching YouTube videos of javelin athletes, Yego is the African record holder for the event with a personal best of 92.72 m. He won the javelin title at the All-Africa Games in 2011 and at the African Championships in Athletics in 2012 and 2014; at the 2013 World Championships he placed fourth, losing a medal in the final round.

[2] Yego became interested in the javelin throw as a youth and later he watched videos of athletes such as Jan Železný and Andreas Thorkildsen on YouTube to help with his technique and to learn how to train at a gym.

[5] He earned his first national call up in 2010 and threw a personal best of 74.51 m to take the bronze medal at the 2010 African Championships in Athletics, which was held in Nairobi.

In respect of this achievement the IAAF (the sport's governing body) gave Yego a six-month scholarship to train alongside elite javelin coaches in Europe, with the aim of preparing him for the 2012 London Olympics.

[14] He won a second gold later that summer at the African Championships, throwing a season best 84.72 m and defeating world leader Ihab Abdelrahman El-Sayed of Egypt.

[15] Yego continued his rise in 2015, winning the Ostrava Golden Spike javelin on 26 May with a new Kenyan record of 86.88 m after his best throw was not flagged as a foul by the judges even though his hand touched the line.