The ball boy who was was apparently kicked by a Chelsea football star during a match boasted about time wasting online before the game.
Charlie Morgan appeared to take part in the Capital One Cup semi-final between the Londoners and Swansea City with the intention to run the clock down.
Tempers flared in the final minutes after the 17-year-old refused to return an out of play ball to Blues forward Eden Hazard.
The Belgian player was sent off after he was seen to lash out at the teenager.
One pre-match tweet on Charlie Morgan's account read: "The king of all ball boys is back making his final appearance #needed #for #timewasting."
Both the player and teenager have been interviewed by South Wales Police but no further action has been taken.
Chelsea manager Rafa Benitez said the ball boy and the Chelsea star exchanged apologies in the dressing room after the match.
"We cannot change the situation. We are disappointed because we lost a player. The best thing for us is to move forward."
Swansea manager Michael Laudrup said he expected Hazard would regret the incident when he viewed it on television.
"I saw it from a very big distance from the bench. I've since seen it after the game. Hazard is a great player. When he sees the images I think he will regret it."