His shot was saved by West Ham’s Spanish goalkeeper Adrian San Miguel del Castillo while he was chased by a steward amid cheers from the crowd on August 16.

Today he apologised for a “moment of madness” as he pleaded guilty to a charge under Section 4 of the Football Offences Act 1991, which states that it is an offence to go onto the playing area without lawful authority or excuse.

He is facing a ban from matches and a fine.

Ben Edwards, prosecuting, told Thames Magistrates’ Court in east London: “At around 4pm in the afternoon the defendant was seen to jump the barrier separating football fans from the pitch and run along the pitch towards the goal.

“He was then seen to kick the football being placed on the ground for a free kick.”

Dunn told police in interview after he was arrested that he had been a West Ham fan since he was a little boy and it had always been one of his dreams to “run on the pitch and kick the ball”, the court heard.

Mr Edwards added: “Now he could say he had done it. He also said now he had done what he wanted to do he is not going to do it again.”

Asked what was going through his mind by District Judge Gareth Branston, Dunn said: “Nothing really – it was just a moment of madness. It was a spur of the moment thing. I just went.”

The judge said he had seen footage of the incident on YouTube and asked: “Were you intending to take the free kick?”

Dunn replied: “No. All I was going to do was run and as I was running I just saw the ball there so I thought I would just kick it.”

He said he was “sorry” for committing the offence and admitted he had drunk around six beers before the match but denied being a “hooligan”, “thug” or “yob”.

Dunn, who works as a receptionist at a hotel, said he has a 10-month-old little boy.

Referring to the prospect of a banning order, he said he expected to be barred for a period, but added: “I was a bit concerned that when my little boy grows up I want to take him to watch the football.”

The judge asked if his mother had “expressed disapproval”.

Dunn said: “At first she was concerned because she didn’t know the consequences, but when she saw the YouTube video she saw the funny side but she has had a go at me, as a mother would.”

The pitch invasion provoked amusement on social media, with one fan saying the effort was better than Spurs star Christian Eriksen’s free kick once play had resumed.

He wrote on Twitter: “Fair play to that pitch invader at West Ham v Spurs. He got the Free kick on target when Eriksen couldn’t.”

The judge will pass sentence later.