Sweden coach Janne Andersson makes no bones about spying on South Korea's training sessions ahead of their game at the World Cup.
The South Koreans responded by swapping players' numbers around to confuse the Swedish "spy" because, in the words of coach Shin Tae-yong, "it's very difficult for westerners to distinguish between Asians."
Surveillance and misdirection has been a big part of the buildup to the Group F game in Nizhny Novgorod on Monday, 18 June.
That's because both teams probably recognise how crucial their opener is with tougher tests later in group play in Russia against defending champion Germany and Mexico.
Andersson apologised to the South Koreans on Sunday, 17 June, over an incident at South Korea's pre-World Cup training camp in Austria, where a member of the Swedish coaching staff got into a closed Korean training session and was told to leave. The Swedish staffer thought the training session was open, Andersson said, and left when asked.
He still tried to gather as much information on the Korean drills as he could.
"He watched from more of a distance as a result," Andersson said.
Andersson didn't comment on allegations that the Swedish staffer in question, Lars Jacobsson, rented a house across the road from the Korean training ground in Austria so he could watch them work out.
He did say Sweden analyses every opponent — mostly by watching their games — and it's fairly routine, but "it's very important that we show respect for opponents, always and in every way. If it has been perceived in another way, we apologise."
He needn't have worried too much about apologising as South Korea's Shin recognised that at the World Cup, every team will try and get an edge.
You always want to know about the opponent. That’s something that we do as part of the staff. I don’t think that that’s bad. We have to understand our opponents. So that’s part of the job that we do.Shin Tae-yong, South Korea Coach
South Korea's response to the Swedish "spy", as Shin referred to him, was to change the numbers the players wore in their warm-up games.
Shin's reasoning behind that was that although South Korea has Tottenham forward Son Heung-min, many of the players play in the Asian leagues and aren't well-known worldwide. So, swapping numbers will make sure the Swedes can't easily identify a player by number.
"We wanted to confuse the Swedish team. Yes, that's why we did that," Shin said. "We heard that there was a Swedish spy."
Asked if he had more "hidden tricks" for the game, Sweden's Andersson responded:
Hidden tricks are only hidden tricks if they are hidden.
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