O Se-Jong’s successes in short track speed skating came primarily as a member of the strong South Korean team. He earned Olympic gold in the relay at the 2006 Torino Games, having won the same event at the World Championships three years earlier. Other relay wins include six World Cup victories and a gold medal at the 2003 Asian Games. In 2006, he was also a member of the squad that earned the gold at the Team World Championships, a now defunct competition. He also medalled in that competition from 2000 through 2003, earning two silvers and two bronzes. O’s biggest individual success came in 2006, when he won a bronze medal in the 1,500 m at the Worlds, joining his compatriots An Hyeon-Su and Lee Ho-Seok a Korean sweep of the podium. At age 33, O Se-Jong was killed in a motorcycle accident when he crashed into a car making a U-turn.