Only a handful of competitions can keep viewers enthralled through three-quarters of an hour of tradition before the first point is even decided.
Yet the intricate traditions unfolding in a small clay ring - mostly preserved for centuries - managed to do just that.
This five-day event at the Royal Albert Hall features four dozen top-tier sumo wrestlers showcasing a sport whose first mention dates back to the first century BC.
London's renowned auditorium has been utterly transformed, complete with a elaborate suspended canopy hanging above the dohyĹŤ.
It is here the competitors, known as rikishi, perform their shiko exercises to banish negative energies, and where they strike their hands to summon the divine beings.
Above all this historical practice, a giant, revolving LED screen - that would fit perfectly at an NBA match - offers the audience all the statistics and footage they could want.
For Sian Spencer, it was a "chance online clip" that first drew her interest a couple of years ago.
This was quickly followed by the discovery of specialized online content for rikishi houses, where athletes reside and practice, waking up early to train, followed by a high protein stew and then an midday rest - all in the service of increasing mass.
Julia and her partner Cezar discovered sumo through a conventional method: a trip to Japan six years ago.
"We saw it as a typical visitor experience, but we actually came to adore the sport," notes the enthusiast.
"After that, we tried to locate groups, information, just to learn more about it," the other fan explains.
Traveling to Asia is typically the sole method to see a top-flight sumo tournament.
This London competition marks only the second time the tournament has come to London - the previous visit was in 1991.
Even visiting the country isn't certain of securing tickets, with current times seeing completely booked tournaments.
For numerous spectators, the London tournament represents the first time they have watched sumo in person - and it doesn't disappoint.
"Watching nearby, you get a understanding of quickness and the force which you can't experience on TV," notes one fan. "Their stature is remarkable."
To achieve victory, one competitor needs to move the other man from the dohyĹŤ or to the ground using physical force.
The most use one of pair of techniques to succeed in this, often in split seconds - pushing, or wrestling.
Either way, the sound of the two rikishi crashing together in the initial contact of the match reverberates around the hall.
The positions right next to the ring are of course highly prized - but also, potentially hazardous.
During one particular match, a large wrestler went plummeting into the crowd - perhaps making those in slightly cheaper seats feel relieved.
Of course, the stature of the wrestlers is one of the primary elements most people consider when they think of sumo.
The venue's management revealed they "had to source and purchase additional seating which can withstand 200kg in weight."
But sumo - for all its popular tournaments - is not without its troubles behind the scenes.
Perhaps the strict life of a professional athlete doesn't look as desirable as it once might have.
Its appeal among young Japanese is also being competed with by different athletic pursuits, while Japan's decreasing numbers will not help.
Not that any of this has worried fans in London.
"Experiencing the tradition and practice that is part of sumo is quite special," fan Sian says. "Now, seeing it in person, you feel like you are more involved."
For other dedicated followers, the intensity "made it so incredible" - as did meeting the fellow enthusiasts.
"Leaving a particularly focused online community and being able to observe numerous sumo fans directly and being able to speak to other people who are similarly enthusiastic as we are - it was absolutely worthwhile."
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