Harry Redknapp fears South Korea are unlikely to allow Yun Suk-Young to take part in Queens Park Rangers’ Play-off Final against Derby on May 24 because he is part of their World Cup squad.

FIFA rules state that May 19-25 is an ‘official rest period’ for all players selected for the tournament in Brazil, with the final recognised date for club competitions being Sunday.

The only exception is the Champions League Final, which also takes place a week on Saturday, meaning QPR are powerless if South Korea ask for Yun’s release. Countries can give players permission to take part in club games during the rest period and Croatia have cleared Rangers’ Niko Kranjcar to play at Wembley Stadium.

It is understood South Korea football chiefs want Yun to join the rest of the squad, who are at a training camp in Paju, north of Seoul, ahead of a friendly against Tunisia in Seoul on May 28.

QPR boss Redknapp is aware of the situation but it is not thought a final decision has been reached on whether Yun, who joined the club in January 2013, will be available for the Play-off Final. However, it is expected South Korea will request Yun’s release because they do not want to lose another left-back after Park Joo-Ho, who plays for German club Mianz, was ruled out of the tournament through injury.

Yun, 24, has become a key part of the QPR squad in recent weeks after returning from a loan at Doncaster. He scored his first goal for Rangers against Barnsley earlier this month and played in both legs of the play-off semi-final against Wigan. The final is dubbed ‘the richest match in world football’, estimated to be worth around £120million to the winners.

Charlton’s Iranian striker Reza Ghoochannejhad and Fulham midfielder Ashkan Dejagah have been told not to swap shirts with rival teams at the World Cup because their country might not be able to replace them.

All the members of Iran’s 23-man squad are under instructions to desist from the post-match ritual, even though the country will earn at least £5million from the tournament.

“We are not giving the players a shirt for every game, the players have to be economical with the shirts,” said Iranian football chief Ali Kafaschian.