South Korea felt duty-bound to defeat North Korea in Olympic Games table tennis Saturday, but admitted they were still none the wiser to solving the mystery of their secretive neighbours.
"We are the same people and we speak the same language but politically we're not very friendly at the moment," said South Korea coach Yoo Nam-Kyu.
"Due to our history we felt we had to beat North Korea, we felt we had to win because we were playing them."
North and South Korea are technically still at war after the 1950-53 conflict and any sporting occasion, pitting the one against the other, always attracts attention, cranking up the pressure on the athletes involved.
But Yoo was unsure who was under the greater pressure to succeed.
"As far as I know they will have more pressure and get more stressed because they lost and people will hear about their defeat," he said.
"Our record is much better than the North, so if we'd lost it would have been much more pressure and stress for our side. But we won because we're better."
Although the two countries do not enjoy good relations on a political level, Ryu Seung-Min, who beat Kim Hyuok-Bong to seal the 3-1 victory, said the players themselves get on well.
"It's not bad, we always say hello because we speak the same language and like us they have also been playing for a long time," he said.
"We always see them at tournaments, so there's no problem. Table tennis is special because last November we had the Peace and Sports Cup invitation matches and Kim Hyok-Bong played with me in the doubles in Qatar.
"I had a good partner. We always have good relationships and good friendship but on court we are at war, we have a table tennis war."
Yoo said the two teams are on friendly terms and speak to each other around the Olympic Village, although there is one subject that never comes up.
"We ask how they are and we just talk about every day life, not political life," he admitted.
"We just say how are you and talk about sports and general things."
But that doesn't extend to a close relationship.
"They haven't told me anything, I don't know about their lives or anything. We just shake hands say a greeting and how are you," added Ryu.
They didn't discuss the match with the media either, opting to push through the press conference zone, straight to the exit door.
South Korea's Oh Sang-Eun had lost to Kim Hyok-Bong in the opening match but Joo Sae-Hyuk levelled the scores after beating Jang Song-Man.
Oh teamed up with Ryu to beat Jang and Kim Song-Nam in the doubles before Ryu scored the winning point in the singles.
South Korea were the favourites, but Yoo said his team's more illustrious standing in the sport had increased the pressure on his team.
"I felt a lot of pressure playing against North Korea. We lost the first match but Joo Sae-Hyuk did very well," said the coach.
"He fought very hard to win so I was relieved after that."
South Korea will play Portugal, 3-0 winners over hosts Great Britain, in the quarter-finals.