Photographs of the pleasantly colourful contrast of Iceland’s Bardarbunga volcano erupting alongside the lights of the aurora borealis provided perhaps the most eye-catching clash in Iceland this week, but it is not the most eagerly anticipated. Unlikely to be as pleasant on the eye, but no less explosive, that particular showdown is scheduled for Saturday, with the fixture generator having unwittingly maximised excitement among Iceland’s football followers by pitting the Premier League’s two potential title winners against each other on the final day of the season. Having played 21 games each, both teams remain unbeaten.

The catchily titled Fimleikafelag Hafnarfjardar (FH) currently top the table with 51 points, two clear of second-placed Stjarnan. A draw will be enough to hand the title to FH and consign their title rivals, best known for extravagantly choreographed goal celebrations that have won them so many fans on YouTube, to the runners-up spot despite not losing a game.

“FH are a bit like Manchester United, while Stjarnan have never won a major title before,” explains Maggi Mar Einarsson, the editor of Icelandic website Fotbolti.net and a midfielder with Leiknir Reykjavik, who won promotion to the top tier last week. “They have been to the cup final in 2012 and 2013 but lost on both occasions. They went to the fourth qualifying round of the Europa League this season but lost to Inter. People are very excited about this, particularly because both teams are unbeaten. They’ve actually moved the kick-off, so all the other games in the final round of fixtures will start at 1.30pm and this game is on at 4pm. It’s live on telly.”

It seems a fitting end to a year in which Iceland established its place on the international football map. Previously best known for featuring in a pub quiz question about fathers and sons featuring in the same international team (Eidur Gudjohnsen famously replaced his father Arnar during a match in 1995), Iceland came within a playoff defeat to Croatia of qualifying for Brazil 2014. For a European island outpost with a population of just 330,000, it was a fairly heroic achievement from which they hope to progress by qualifying for Euro 2016. The imminent arrival of the snow means their European qualifier against Holland later this month will be the final football match of any significance played in the country this year.

Before that, the domestic title will be claimed by one team of Icelandic Invincibles, while another could finish as runners-up. As unlikely as it might seem, this would be far from unprecedented. Despite going unbeaten all season in 1978-79, Italian side Perugia still finished second in Serie A behind Milan, who lost three times. Spartak Sofia (1951), Benfica (1977-78), Galatasaray (1985-86) and Red Star Belgrade (2007-08) have all suffered the ignominy of finishing second in their respective leagues despite going undefeated all season. Unlike in Iceland, however, the teams who finished above them were all beaten on their way to winning the title.

Nor is it unprecedented for two different teams to have gone unbeaten in a completed season, with Happy Valley getting pipped to the title by South China in the 1985-86 Hong Kong First Division League without either side tasting defeat. Should the same fate befall Stjarnan on Saturday, they can at least take comfort from the fact that having completed 22 matches compared to the 18 played by Happy Valley, their failure will have been more epic. Whatever the outcome of Saturday’s match, it will be attended by a record crowd at FH’s small Kaplakriki Stadium.

“You might laugh, but there’ll be about 6,000 people,” explains Einarsson, laughing. “But remember that only 330,000 people live in Iceland. FH is from Hafnarfjordur, which is a town of 25,000 people and Stjarnan is from Garoabær a town of 14,000 people, so to get 6,000 people in to watch the game is pretty good. Both towns are very near each other so Stjarnan fans can walk to the game if they wish.”

In a country where every football supporter has an English team, FH boast fancy dan foreigners in former Manchester United youth team player Sam Hewson and former Rangers and Scotland Under-21 international Steven Lennon. Their left-sided utility man Sam Tillen also played for Chelsea’s youth team, but hasn’t featured in this campaign after breaking his leg in March during pre-season training. Barring a handful of Danish imports, Stjarnan’s squad is comprised almost entirely of Icelandic natives, a whopping four of whom are famous enough to have their own pages on Wikipedia. If their status as plucky underdogs doesn’t get neutrals rooting for them, then the prospect of seeing whatever carefully rehearsed celebration they unveil in the event of their first league title win surely will.