KSI and Logan Paul Image Credit: Supplied

York Hall, in London’s Bethnal Green, is one of Britain’s oldest boxing venues. Opened in the 1920s, it still hosts professional bouts in front of audiences of 1,200 people.

But in its near-century, the venue has never seen anything like the event that took place last week, when more than 1,000 teenagers queued to watch two of YouTube’s biggest stars — and rivals — trade insults ahead of their highly publicised boxing match next month.

KSI, a Fifa gamer turned internet personality, and Logan Paul, who found fame posting skits on Vine and is best known for mocking the dead body of a suicide victim in one of his videos, are big names on YouTube, with almost 20 million subscribers each. They’ve been sparring verbally for months, and after KSI defeated fellow YouTube star Joe Weller in a boxing match in February, fans began piling on the pressure for KSI and Logan to have their turn in the ring.

KSI ‘s handout photo pictured him in a Muhammad Ali pose, over a knocked down Paul — as happened in their first round in London last week when Paul conceded defeat in their insult-trading round.

The whole thing is very silly, very theatrical and almost completely incomprehensible if you are older than 20. It is also huge. The fight will take place in the 21,000-capacity Manchester Arena in August, with tickets costing between 30 pounds and 150 pounds, and it will be streamed on YouTube’s pay-per-view platform for GBP6, though the company has distanced itself from the event and is not commenting on the fight.

KSI, from London, will be defending his self-proclaimed title of YouTube boxing champion (claimed earlier this year following a third-round knockout of Weller) against his American foe Paul, with various members of the pair’s “squads” — including their brothers, Deji Olatunji and Jake Paul — also agreeing to fight each other.

When KSI arrived on stage he began hurling abuse — a mix of theatrical and apparently genuine insults — at Logan who was too cowed to fight back.

Outside York Hall, an hour before the press conference is due to start, the queue is round the corner and down the street, with those at the back being assured they have no chance of getting in but continuing to queue. They are here for the chance to see their icons, and in this multicultural London crowd, that overwhelmingly means KSI and his squad, the Sidemen.

In fact, when one of Logan’s team — the Logang — drives past the entrance in a flash car, a spontaneous chant of “[expletive] Jake Paul” begins almost immediately, not dying down until the car is well down the street and into the side entrance.

It is not hard to see why they rub people up the wrong way: the pair got their start with six-second pranks on Vine, before moving on to bigger and better things, both virtually, trading Vine for YouTube, and physically, moving from Westlake in Ohio to LA.

Logan Paul stands pretty on KSI’s photograph — wishful thinking perhaps given his teary getaway from KSI’s barrage of insults last week.

Since then, they have been constantly in the press for their antics, from manufactured drama for their YouTube channels to real drama with their neighbours.

Last July, Jake’s $17,000-a-month (GBP13,000) rented home played host to a stunt involving a burning pile of mattresses that was the final straw for many of those living near him.

Logan has perhaps been less deliberately obnoxious, but the same thoughtless attitude has brought him as much trouble. In January, YouTube disowned him and demonetised his channel for a stunt in a suicide hotspot in Japan that saw him laughing and joking around a body.

Both KSI and Paul have been constantly in the press for their antics, from manufactured drama for their YouTube channels to real drama with their neighbours.

Although billed as a press conference, the real audience were at home watching, which meant the whole affair was more of a pastiche of a boxing press conference, as filtered through news broadcasts, films and highlights of previous matches.

The rivalry, though profitable, also seems sincere.

When KSI arrived on stage he picked up Deji’s lead, hurling abuse — a mix of theatrical and apparently genuine insults — at Logan, but the older Paul brother is either too outgunned by the crowd, or too cowed, to fight back.

He sits, mostly in silence, as the insults become personal — KSI turned at one point to the father of the Paul clan, himself a minor internet celebrity. Eventually, Logan drops the mic and walks out, seemingly on the edge of tears, cutting the event short.

The crowd clears out, and Logan flees in a bright yellow Rolls-Royce. But it is not quite the end: hoping to see more of KSI, half the audience ascends the stairwell of a neighbouring housing estate, while the rest cram up against the gates of the car park. The YouTubers cannot get out, the teens cannot get in, and there is gridlock — until someone starts chucking construction debris from the roof, the stars are shepherded back in, and the police are called.