With the lights adjusted and the cameras rolling, the production team gives Joe Smith his cue. In five seconds, he will be broadcasting live to a couple thousand people. Mr. Smith’s mind, though, is elsewhere. “Slate is definitely the best way to build a roof,” he mutters to his co-host, Jay Mottershead, as the countdown hits three. “All these years on, they haven’t topped it.”

And with that, they are on air. They will remain so for the next four hours, essentially uninterrupted: a broadcasting endurance test staged in a subterranean studio, all exposed brick and industrial lighting, in the middle of Manchester’s achingly hip Northern Quarter.

Before they have finished, they will have touched on subjects as diverse as: the slightly alarming frequency with which Mr. Mottershead has nightmares; the declining popularity of lemon curd; and the story of a man who attends Mr. Smith’s gym exclusively to read vintage copies of “Cars” magazine.

Occasionally, their freewheeling, faintly anarchic conversation to be interrupted by what is supposedly the purpose of the evening’s activity: keeping track of the game between the soccer team they support, Manchester United, and the Danish champion, F.C. Copenhagen.

That is, after all, what will attract more than 100,000 people to their livestream over the course of those four hours. It is the diversions and the tangents and the stream of consciousness about roofing, though, that will keep them there.

Hard-Core Community

The concept of watching two people watch a soccer game might sound like a distinctly postmodern form of entertainment, a close cousin of the gaming streams that proliferate on Twitch and the unboxing videos that for some reason captivate children on YouTube.

In soccer, though, the form has deep roots. The idea of making most games available to watch on television, after all, is a relatively recent one. In Britain, home to the Premier League, many games continue to be blacked out, in the interest of protecting in-stadium attendances.

Barred from showing those games, broadcasters have for years had little choice but to find creative ways to keep viewers up-to-date on what is taking place in them. Most have settled on the format pioneered by Sky’s “Soccer Saturday” — launched in the 1990s — in which an array of former players sit in a studio, watching feeds of the games only they can see, and update viewers on key moments in real time. (Think of the N.F.L.’s popular Red Zone channel, only without seeing anyone actually playing football.)

The form of the show that Mr. Mottershead and Mr. Smith host on Stretford Paddock, the Manchester United fan channel they co-own — or its counterparts on outlets like The Redmen TV (Liverpool) and We Are Tottenham TV (self-explanatory) — is essentially the same. The function, though, is distinct.

Most of their viewers, Mr. Mottershead said, are also watching the games, either legally or illegally. “They turn the commentary down and listen to us instead,” he said. They do so because they want a much more narrowly focused product: Stretford Paddock’s audience only wants updates on Manchester United, for example, not news about anyone else who is playing at the same time.

And, crucially, they want those updates delivered not by the compromised and biased mouthpieces of the mainstream media — what they see as retirees protecting their friends and business interests, or commentators with the nebulous but definite prejudice against their club — but by dyed-in-the-wool fans like them. “We might disagree on things,” Mr. Mottershead said. “But we all want United to do well.”

Still, after more than six years leading watchalongs with Mr. Smith, Mr. Mottershead has come to believe that what draws in fans is not simply a matter of having their obsessions met and their biases confirmed.

What his viewers are looking for, he thinks, is simple. They want someone to watch the game with them.

Viral Empire

The part of the soccer industry that is made for fans and by fans is necessarily tribal. Every club essentially exists in its own silo. The biggest names in the Manchester United content universe will be largely alien to those who follow Liverpool, just as celebrated Arsenal podcasters will have little or no resonance to Tottenham supporters.

The crowning exception is Mark Goldbridge, soccer’s 44-year-old livestream kingpin and the genre’s only real crossover star. It is not just that his fan channel, The United Stand, currently has 1.77 million YouTube subscribers. It is that almost every time Manchester United loses (or draws, or concedes a goal), he is liable to reach many millions more.

Footage from Mr. Goldbridge’s streams reliably goes viral: rants that are by turns splenetic, wildly N.S.F.W., and vaguely surreal. He will howl that Manchester United’s defense has “all the resistance of a papadum catching a bowling ball,” say, or that the club is accidentally employing “a team of slow giraffes.”

Quite what it is about Mr. Goldbridge that has made him so prominent is difficult to pinpoint, and he offered no clues: He declined through his representation to be interviewed for this article, on the grounds that he is currently exploring opportunities away from “the watchalong space.”

In interviews, Mr. Goldbridge has accepted that there is an element of cringe comedy, in the style of David Brent or Alan Partridge, to his delivery. Peter McPartland, a host on Toffee TV, a channel dedicated to Everton, agreed. “There is an awkwardness to him that makes him funny,” he said.

Whatever it is, it is undeniably effective. “He has built an empire,” said Paul Machin, a founder of The Redmen TV, the Liverpool fan channel. The problem is less his success, other hosts said, and more in the copycats he has inspired.

“People see his videos going viral,” Mr. Machin said, “so now there are a lot of Manchester United watchalongs where people you’ve never seen before are kind of performing their anger.”

The economics of the internet, in theory, incentivize virality. In an industry in which there is a direct correlation between clicks and revenue, going viral is held to be both the greatest prize and the ultimate purpose of all online content.

Those who earn their living from fan channels, though, see that kind of attention less as a goal and more as a danger. “We don’t want that virality,” said Ben Daniel, who founded We Are Tottenham TV with his brother, Simon, in 2017.

Clips that break tribal lines tend to do so by attracting a considerable proportion of “hate watches,” he said — views from fans of other clubs relishing another team’s suffering. But those are not people who might hit the like button, or subscribe. Virality, it turns out, brings the wrong sort of fame.

Parasocial

On the surface, the rewards for watchalong fame are thin. YouTube’s algorithm is weighted toward shorter videos, not hours of broadcast. The platform’s chats, which allow viewers to append payments to their comments or questions, drive only a couple of hundred dollars of revenue.

The benefits are largely second-order ones. They are worth doing, Mr. Smith said, because they can drive subscriptions. Mostly, though, they do them because “it would be weird not to: The game is the culmination of everything we talk about.”

He and Mr. Mottershead are old hands by the standards of the genre: Stretford Paddock has been doing watchalongs for almost a decade. Most of the newer versions trace their origins to the pandemic, when social distancing rules kept fans from attending games in person.

Before then, fan channels focused on giving supporters who could not or did not attend games a digital version of the experience: a taste from outside the stadium, and inside the crowd, before, during and after games.

With the stands empty, that was not possible. All that was left was to offer running commentary on the games that they, like every other fan, were watching on television.

When fans returned to the stands, though, the channels noticed there was still a sizable audience craving that type of in-game coverage. “It was so popular that we couldn’t drop it,” Mr. Machin said of The Redmen TV’s experience.

Creators of Premier League watchalongs said they all appeal to roughly the same audience, distinguished only by tribal allegiance: fans generally between 16 and 35, though with a substantial proportion who are just a little older. A slender majority live in Britain, but there are healthy constituencies in Ireland, the United States and Australia, as well as whichever country a given team’s stars call home. Tottenham, for example, has a sizable following in South Korea thanks to the club’s beloved captain, Son Heung-min.

They are all watching, too, for much the same reason. “People want to feel that connection to their clubs,” Mr. Machin said, wherever they happen to live.

Watchalongs create a different sort of bond: a form of what psychologists call a parasocial relationship. Viewers want their biases to be reinforced. They want to know how other, like-minded fans are reacting to the games. But they also want the digressions, the asides about roofing and nightmares and cultural appropriation as it relates to hairstyles.

They are, after all, watching from home, all around the world, each of them locked in their own little silo. What they want, more than searing insight or expert analysis or even a cheap laugh, is a connection to people who are doing exactly the same thing.

Mr. Mottershead and Mr. Smith are not trying to offer them detailed commentary. They are trying to recreate the feeling, Mr. Mottershead said, of “watching the game with your mates.”