Amir Khan
At 17, Amir Khan made an enormous impact in the lightweight division of the Olympic Games in Athens, beating European champion Dimitar Stilianov on the way to a silver medal. 
He was attempting to become the youngest boxer since Floyd Patterson in 1952 to win a gold medal, but lost in the final to the very experienced Cuban Mario Kindelan.   He was also the youngest British boxer to compete in the Olympics since 1976.
Khan was a 13-year-old schoolboy when Britain’s Audley Harrison won gold in the Sydney Olympics in 2000 which enthused him to try to emulate that achievement.  By June 2004, Khan was already European and World Junior champion after a series of victories in Lithuania and Korea.  In the World Championships, he was named best boxer of the tournament after winning the lightweight division.
The 17-year-old won the first round in the Olympic final against Kindelan, but the experienced Cuban established his dominance in round two, picking off the teenager with counter attacks.  Although Khan closed out in typical aggressive style, he could not stop the Cuban winning a third straight title.