Eagle-eyed Chelsea fans have spotted Antonio Rudiger delievering a painful-looking slap to the bare back of team-mate Trevoh Chalobah as the pair celebrated their Club World Cup triumph in the changing rooms with the rest of the squad.
The Blues saw off Palmeiras 2-1 on Saturday in Abu Dhabi, thanks to an extra time penalty from Kai Havertz three minutes from the end after Romelu Lukaku's earlier 54th-minute strike in the regular 90 minutes had been cancelled out.
The win sparked jubilant celebrations in the dressing rooms afterwards, with Thomas Tuchel's men filmed jumping up and down on the club's official TikTok page.
But during the celebrations, Rudiger can be seen getting down from one of the dressing room benched to then sneak behind a topless Chalobah, where he then delivers an almighty slap to the back of the young Englishman.
The slap can be heard among the cheering Chelsea players before Chalobah lets out a huge scream much to the amusement of Blues supporters that clocked on to Rudiger's micheavous antics.
Rudiger can then be seen sneaking to the front of the group after committing the hilarious but devious prank on his team-mate.
However, while Rudiger appeared to get away with it, Chalobah has hilariously vowed to get his 'revenge soon' after watching the video back on Twitter.
The clip, which has been doing the rounds on social media, has left Chelsea fans in hysterics with many labelling Rudiger as 'troublesome' and a 'menace'.
One fan tweeted: 'Rudiger is genuinely a menace to society.'
While another added: 'Rudiger is trouble.'
Another fan compared Chalobah's scream to one found on Tom and Jerry cartoons.
They said: 'That scream was the best, straight out of tom and jerry.'
Tuchel's side qualified for the event after winning the Champions League last season but had previously lost the final in 2012 - the only occasion a European side has failed to win the Champions League and World Cup double since 2006.
Victory for the west London outfit sparked celebrations among the playing staff as they danced on the pitch and showed off their medals at the Mohammed bin Zayed Stadium.
Havertz, who also scored the winner in the Champions League final last summer, was among those leading the celebrations as he took part in some brief dodgy dancing with team-mate Mason Mount on the pitch.
Mount although involved with the celebrations had a heavily bandaged right foot having been taken off injured in the 31st minute due to an ankle injury that could now keep him sidelined for a lengthy spell.
The 23-year-old looked in serious discomfort during the post-match celebrations, though, and did not want to put any weight on his right leg, hopping around and leaning on another injured Chelsea man, Ben Chilwell.
Chilwell, along with Reece James, was also among the Blues cheerleaders after the game, and uploaded dressing room pictures of the jubilant celebrations.
The duo were pictured holding their winners' medals from the tournament even though injury prevented them from playing a single minute in the Middle East.
While all the players managed to get their hand on winners' medals and the Club World Cup trophy itself, centre-back Thiago Silva left the tournament with slightly more to celebrate than his team-mates.
Even though the centre-back gave away the penalty for Palmeiras' equaliser for a hand ball in the final, he was awarded the Golden Ball award to crown him the best player at the tournament.