The 32-year-old won six Olympic golds, three for South Korea and three for Russia.
Olympic short track great Viktor Ahn has retired from speed skating.
The 32-year-old won six gold medals and no fewer than 20 world titles in an illustrious career.
The skater, born Ahn Hyun-soo in the South Korean capital Seoul, sprung to prominence as a 16-year-old at the 2002 Salt Lake City Olympic Games.
He reached the final of the 1,000m, but fell in the final famously won by Australia's Steven Bradbury.
Four years later, Ahn won his first of three golds at Turin 2006.
He followed up with victories in the 1,500m and 5,000m relay and took bronze in the 500m.
But at the 2006 World Championships in Minneapolis, Ahn collided with team-mate Lee Ho-suk in the 3,000m final.
The incident amplified tensions within the squad and his father, Ahn Ki-won, struck the vice-president of the Korean Skating Union on their return to Incheon International Airport.
After an uneasy truce, Ahn won a record fifth consecutive overall world title at Milan in 2007.
But in January 2008, he fractured his knee when he crashed into a fence during training.
Ahn was not the same force on his return and he missed out on qualification for Vancouver 2010 after finishing only seventh overall at the national team trials.
In 2011, the Russian Skating Union announced that he was seeking Russian citizenship with Ahn's father saying his son was "deeply hurt" in Korea and that he "had no support and was actually ostracised".
Taking the name Viktor, Ahn returned with a vengeance at the Sochi Games.
As he did in Turin, Ahn won three gold medals - including a first in the 500m - and one bronze.
His success led to then South Korean President Park Geun-hye ordering an inquiry into how Ahn had ended up competing for a Winter Games rival.
Ahn had hoped to bow out in the land of his birth at PyeongChang 2018, but he was barred with Russian athletes under suspicion after the McLaren report had detailed systematic doping at Sochi.
His last competitive event was the European Championships in January 2018 where he took silver in the 500m in Dresden.