Liverpool manager Jurgen Klopp wore Cristiano Ronaldo branded boxers for the Champions League final against Real Madrid in 2018.
The Reds were beaten 3-1 by Madrid in Kyiv, with a memorable double from Gareth Bale helping to secure victory for the Spanish side.
It was Liverpool's first Champions League final since 2007 and Klopp opted for a unique way to relieve his team of any tension ahead of the match.
"We saw he was wearing the boxer shorts of Cristiano Ronaldo," said Wijnaldum.
"He did the meeting with his shirt stuffed inside his 'CR7' boxers. The whole changing room was on the floor laughing their heads off.
"That really broke the ice. Usually, in those situations, everyone is serious and concentrated. But he was relaxed and made this joke.
"He's done hundreds of jokes like that. If you see that your manager is really confident and relaxed, it will have an effect on players.
"He is a father figure in those things for the players. With his jokes and his body language, he takes the pressure off players."
James Milner has since confirmed that Klopp's unusual choice of underwear was intentional.
"That was his way of trying to relax the boys," Milner told the Daily Mail.
"Around games, he'll think, 'What is the narrative?' Like if something’s on the lads' minds that they’ve seen on social media.
"He's good at nipping things like that in the bud."
While Liverpool lost in Kyiv, they would go on to win the Champions League the following season – beating Tottenham 2-0 in the 2019 final in Madrid.
Klopp reached his third Champions League final with Liverpool last season but was once again beaten by Madrid, with Vinicius Jr's goal securing a narrow 1-0 win for the Spanish side in Paris.
Liverpool booked their spot in the knockout stages of this year's competition with a 3-0 win over Ajax on Wednesday.
Klopp's side next face Leeds United at Anfield in the Premier League on Saturday.
Featured Image Credit: Alamy
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