Four years ago he was playing against journeymen pros like giant Jon Parkin of Fleetwood, Jack Redshaw of Morecambe, Torquay’s Billy Bodin and the League Two beast that was Adebayo Akinfenwa at Gillingham.
Tomorrow, he pits himself against the finest talent England has to offer, Wayne Rooney, Jamie Vardy, Harry Kane, Daniel Sturridge et al.
Just a few thousand spectators watched Kari Arnason as he did battle in 33 games for Rotherham United in the basement division, often against some of football’s most rugged combatants.
Now the eyes of Europe are on the cultured centre-half as he and his Iceland teammates face Roy Hodgson’s men with a place in the quarter-finals of Euro 2016 at stake.
“Carnage,” he said, with an involuntary shudder, looking back on that first season with the Millers when every match was a physical test.
“The proudest moment of my career,” he says, with a glint in his eye, looking forward to the challenge lying ahead at the Allianz Riviera in Nice, France.
The 33-year-old has come a long way since being lured to New York Stadium by Steve Evans in 2012 after a stint in the Scottish Premier League with Aberdeen.
It wasn’t only his 6ft 3in frame which made him such a big figure for the Millers. His class stood out in his 130 games as he played his part in successive promotions from League Two to the Championship and helped them survive in the second tier before moving to Sweden for Champions League football with Malmo.
“In terms of the best signings I’ve ever made, Kari has to be right up there,” Evans, who parted company with Rotherham last year, said.
“He was magnificent for me. His manager, Craig Brown, when Kari came out of Aberdeen, told me he could play for the Red Lion or he could play for Arsenal. Depends what his head’s like! More weeks than not, he had the Arsenal head on!”
“Arni”, as he was affectionately known by fans, was the most gifted Millers player of recent times, with a touch and ability to see things that belonged in the Premier League. He was nearly 27 by the time he arrived in England with Plymouth Argyle and would surely have played in the top flight had he been discovered earlier.
The higher the standard, the better he plays.
At Rotherham, he was one of the lads but also one on his own. He has a degree in business and the intelligence, guts and character to do things his own way.
Many was the time I’d walk past the assorted ranks of gleaming Mercedes, Audis and Range Rovers on my into a press conference at the Millers’ Roundwood training complex to see Arnason waving to me across the car-park as he pulled his kit from the boot of his four-year-old Volvo.
The progress of him and Iceland - population 330,000 and the smallest country competing - is the story of the Euros so far.
Arnason was born in Sweden when his Icelandic parents were studying there but says Iceland is “100 per cent” his nation. He won his 50th cap, a long-held goal of his, in the 2-1 win over Austria which saw the minnows finish second in Group F to set up the clash with his ‘second’ country.
“I’ve always supported England at big international tournaments when we haven’t been playing,” he said. “It’s a dream come true. But we go into the game to get a result. We believe in our ability.”
Evans loved him, but Arni had the ability to now and again make a gaffe which was completely out of keeping with his extravagant skills.
On such rare occasions, the manager, who took defeat so badly it would twist him up inside, would begin his after-match press conferences with: “I’m not blaming one individual or naming names, but drawing when we should have won is hard to take.”
He would end them: “Let’s be honest, if Kari Arnason heads the ball away as he’s supposed to do then we win that match 1-0.”
The day after the headlines, a stern-faced individual with a slighly foppish fringe would be waiting outside his boss’s office door ready to state his case. And Evans respected him for it.
He once attempted a clearance in time added on against Fulham which bounced off a teammate’s backside and went out for a corner from which the Londoners scored to earn a 3-3 draw.
Evans learned to laugh about it. Eventually. Seven months later when Championship safety had been assured.
King Kari was a brilliant, combative player for Rotherham and maybe even better as a holding midfielder, where he could show the true range of his vision and passing, than in his usual position at the heart of the defence.
Left-back Joe Skarz, who played with him in Leagues Two, One and the Championship, said: “I knew he was class from the game when I arrived. He was sitting in front of the back four doing ‘Cryuffs’ on the edge of our box.
“Him and Morgs (centre-half Craig Morgan) complemented each other so well.”
He has never been scared to say exactly what he thinks and delivers his message in the plainest possible way. One pre-season friendly at New York in 2013 when striker Daniel Nardiello, as was often the case, failed to chase a ball out of defence brought a rebuke so loud and strong mums and dads were covering the ears of their kids.
His English is perfect. As are his swear words.
As a player, he could be pure poetry.
“His reading and understanding of the game are fantastic,” Morgan said. “He has a great appetite for winning. He is so, so comfortable on the ball and an excellent passer.”
Already, Arnason has two man-of-the-match awards in France, including one from the 1-1 draw with Portugal where he did more than anybody to keep Cristiano Ronaldo out of the game.
He dealt with the Real Madrid attacker in the same clever, committed, unflinching manner that Rotherham supporters became used to seeing and afterwards dismissed him with one of the quotes of the tournament.
Not even a superstar gets any change out of Arni if he “fannies around and dives about”.
Ronaldo said Iceland would do nothing in the competition. Arnason shot back: “He’s a fantastic footballer but he’s not a gracious human being.”
Drawing that game exorcised the ghosts of Real’s 8-0 mauling of Malmo in the Champions League last December, when Arni’s central defensive partner, Felipe Carvalho, wasn’t up to the task and Ronaldo scored four times.
It also gave Arnason an extra degree of satisfaction to quieten the pouting Portugeuse because decency matters to him.
“He was a genuinely a nice guy,” Skarz said. “He went out of his way to always make me feel comfortable.”
The best player Arnason has ever come up against? Not Ronaldo. Not Cod Army or Gills luminaries Parkin or Akinfenwa.
“Zlatan Ibrahimovic,” he said. “He’s so big, strong and technically gifted that when he’s on his game he’s virtually unplayable.”
The Swedish talisman is gone from the competition, ousted in the group stages. Arni and his pals are still there.
“This is extra sweet for us,” Arnason said. “We’re a tightly-knit group and what we’ve done is fantastic. It’s extra fun to do it besides my best friends.”
And, just in case you think he’s suddenly gone all soft: “Ronaldo? What else can I say? Sore loser. Tough sh*t.”