Asian Games organisers played the North Korean national anthem for the South Korean men's hockey team on Friday, later apologising for the blunder.
South Korean officials were left angered by the latest mishap to hit the Games ahead of Saturday's opening ceremony in Nagoya.
South Korea thrashed Bangladesh 5-0 but beforehand, instead of their national anthem, the song belonging to North Korea rang out.
The players from South Korea, who had lined up to listen to their anthem, looked at each other bemused.
Organisers then played Bangladesh's anthem, before playing the South Korean anthem later, the South's Yonhap news agency said.
However, the referee ordered players on both sides to shake hands with each other and to start getting ready to play before the anthem ended, it reported.
A stadium announcer apologised for the blunder but Min Tae-seok, coach of South Korea, was deeply unimpressed.
"This is a really serious problem. When we protested, they said, 'We're sorry. It wasn't that it wasn't prepared, there was a mistake on the part of those responsible for playing it'," he said.
"But this is something that simply should never happen."
An official from South Korea's Olympic committee said they were trying to find out what happened.
"We are currently looking into the matter to verify the exact facts," the official told AFP.
The build-up to the Games has been overshadowed by complaints from teams about the quality and amount of accommodation.
Some teams were also stranded at the airport for up to six hours when they landed this week.
