Heimir Hallgrimsson is looking to upset England again with Ireland

Eight years - or 98 months - or 2,992 days - ago, the England men's football team reached one of their lowest moments of the modern era.

Morale was hit and miss during Euro 2016, but the game had started well, with captain Wayne Rooney, debuting for some reason in midfield, netting from the penalty spot just four minutes into the round of 16 tie.

England's lead, however, lasted for just two minutes. Ragnar Sigurdsson, who would go on and play for Fulham, equalised, and Kolbeinn Sigborsson would put an end to Roy Hodgson's damp spell as England manager 12 minutes later.

Iceland condemned the Three Lions to what is widely regarded as one of their worst-ever defeats that day. England were absolutely torn into by fans and the media, and the reset button would be pressed in the form of Sam Allardyce, and, soon after, Gareth Southgate.

It was a momentous result in Iceland's history. Celebrated nation wide by the 335,439 people in the Nordic country, it will be remembered forever. One of the managers, and men, responsible? Heimir Hallgrimsson. And now he's back.

After Iceland's win on that June night, they would lose to France in the last-eight. But Hallgrimsson, who was joint coach of the side alongside Lars Lagerback, became sole manager, with his partner taking charge of Norway.

The high continued through to the 2018 World Cup, with Iceland reaching their first ever world tournament, but they would finish bottom of a group of death including Argentina, Croatia and Nigeria.

Hallgrimsson would resign. The end of an era, but his name etched in history. But his coaching career continued. Over the years, a little less profile, his journey would go on, and eventually come full circle.

England are in a much better place now. An uncertain one, perhaps, following Southgate's exit, but they are one of the world's best. It was a World Cup semi-final and two European Championship finals under the 54-year-old - a side far away from the slums of 2016.

This weekend, they will kick off the Lee Carsley era. It's not known how long that will last - Carsley is in interim charge for now - but the former Ireland midfielder is keen to make his mark.

There's a lot to Saturday's game in Dublin. The start of a new Nations League campaign, Carsley, Jack Grealish and Declan Rice returning to their old stomping ground, and the lesser-focused narative of Hallgrimsson surfacing again.

He is now in charge of the Ireland team. A bit of a rogue appointment, perhaps. The likes of Ole Gunnar Solskjaer and Roy Keane were linked with the role. But the Irish FA would turn to Hallgrimsson in a surprise to the fans.

Ireland supporters are unsure on the appointment, but anything rather than Stephen Kenny is a relief for most. 'A young and exciting team that has genuine potential,' Hallgrimsson said of what he inherited upon taking the role. Reasons to be cheerful.

Upon leaving Iceland, Hallgrimsson took a few months out of the game before moving to Qatar, taking over at Al-Arabi.

There, he finished sixth, seventh and seventh - out of 12 - in the league table, before moving on again and having over a year out of the game.

15 months on, he would make his return to international football with Jamaica. Mostly, his reign was successful. But, earlier on this year, he would lead the Reggae Boyz at the Copa America, and things once again didn't go to plan.

With a team including the likes of Leon Bailey, Michail Antonio and Demarai Gray, hopes were reasonably high, but defeats by Mexico, Ecuador and Venezuela left them pointless, bottom of their group, and, eventually managerless.

But Hallgrimsson he wasn't out the game long. Just 10 days after leaving Jamaica, he would take on the Ireland job, almost as if the FA were waiting for their person, and he would soon be back to work.

His story doesn't stop there, though. He played in his native Iceland during an on-field career, but that was only a side hustle, really.

He spent six years attending Reykjavik University and trained to be a dentist. He signed up with his friend, planning to change what he was learning later, but that never happened. 'He's always smiling, really professional and really good at what he does,' one long-term patient told The New York Times.

He had, at times, planned to go back to dentistry full time, but couldn't stay away from football. But that hasn't stopped him practicing his craft - in 2016, he cared for a player who had a tooth knocked out during a game he was watching from the stands, putting the tooth back in place and then fixing it at a nearby dental office.

This weekend, however, Hallgrimsson will know the drill. It's one of the biggest fixtures on the Irish football calendar. Beat the Three Lions again, and he will be looking for more than a plaque to celebrate his achievements.

As the fixture edges closer, the history of Hallgrimsson and what he did to England eight years ago will, by word of mouth, surface more and more. Carsley and Co will be keen to avoid a repeat appointment of that day, but they have other things to think about too.

With music on the bluetooth speakers, his defenders looking to fill the gaps to keep England at bay and his attackers aiming to show a bit of bite at the other end too, Hallgrimsson isn't lining his men up in Dublin to make up the numbers. He wants to succeed and pull out a hefty upset one more time. Brace yourselves.