SEOUL, South Korea — When the short-track speed skater Viktor Ahn waved the Russian flag on his victory lap and sang the Russian national anthem on Saturday after winning the gold medal in the men’s 1,000 meters at Winter Olympics on Saturday, it was a poignant scene for South Koreans.

Mr. Ahn, whose Korean name was Ahn Hyun-soo, was one of the best skaters South Korea had ever produced, winning many medals for his birth country, including five world championship titles in a row and three Olympic golds. Everyone knew his name in South Korea, where Olympic gold medals are strong symbols of national pride and their winners are looked on as patriots.

“As a Korean, I wish he were singing the Korean national anthem,” Mr. Ahn’s father, Ahn Gi-won, told the South Korean news agency Yonhap in Sochi, Russia. “But however he tried in South Korea, he could have no opportunity to recover his reputation.”