They've not just done it but they've achieved it with two games to spare.
Thanks to a point at Old Trafford and Tottenham's failure to beat Chelsea at Stamford Bridge on Monday night, Leicester City have won the Premier League for the first time in their history.
No one expected the Foxes, who were bottom of the Premier League for 19 matchdays (or to put it in other terms: half a season) last season, to do what they have just done.
But they aren't the only club to completely sweep logic out of the way and cause a title shock in Europe's other Big Five leagues.
Hellas Verona
This season has been a disappointing one for Hellas Verona. Bottom of Serie A and already assured of relegation to the second tier, it's a far cry from 31 years ago when they surprised everyone and won what could then be considered the strongest league in the world back in 1984-85.
Promoted to Serie A after the 1981-82 season, they impressed with top half finishes in the following two campaigns.
But no-one could have expected Verona to rise above the likes of Juventus, Inter Milan and a Roma side which had just reached the European Cup final in 1984.
But that's exactly what they did in '85 with Juventus and Roma finishing sixth and seventh respectively and Torino finishing as closest challengers ahead of Inter.
For the first and only time, Hellas Verona would be champions of Italy before slipping back into obscurity and ultimately relegation in 1990. It was good while it lasted though.
Kaiserslautern
Over the past 20 years, Bayern Munich have shown that they can be beatable when it comes to top honours in Germany. At times Borussia Dortmund have enjoyed title wins in their down years.
Another time it was another traditional big club in the shape of Werder Bremen (2004). Other occasions saw Stuttgart (2007) and the Volkswagen backed Wolfsburg (2009) enjoy league title wins.
Olaf Marschall with Germany in 1998. Picture by: Matthew Ashton / EMPICS Sport
But none of those could match what happened in the 1997-98 season as 1. FC Kaiserslautern, who are a club with plenty of tradition and won the Bundesliga in 1991, pipped Bayern Munich to the Bundesliga title by two points, fired by the 21 goals of Olaf Marschall.
But the most remarkable thing about the 115-year-old club from south-west Germany that season was that they were playing in the second division the previous campaign, thus they won the second tier and top flight titles in consecutive seasons.
In some ways, that almost mirrors Leicester who were bottom of the top flight one year before going on to win the Premier League.
Deportivo de la Coruña
As Sid Lowe, Spanish football correspondent for The Guardian explained to Team 33 in March, it's easy to forget that the Deportivo side which won La Liga in 1999-00 had been preceded by 'Super Depor'.
The latter side, which included star names like 1994 World Cup winner Bebeto, was the La Coruña which enjoyed relative success in the early-to-mid-90s by winning the Copa del Rey and coming close to league wins.
The 1993-94 was particularly poignant as they lost La Liga to the Barcelona Dream Team on goal difference with this missed penalty on the final day against Valencia swinging it:
But by the 1999-00 season, Depor had slipped back into the chasing back, finishing 12th and 6th in the two preceding seasons respectively.
However, their single title victory came in rollercoaster fashion, managing to lose 10 league games and still emerging triumphant above Barcelona and Valencia by points, while that year's Champions League winners Real Madrid were back in fifth.
While Depor enjoyed glory at the start of a second great era for the club which featured no further La Liga wins but plenty of European football, the 1999-00 season was also remarkable in another way as traditional sides like Sevilla, Real Betis and 1995-96 champions Atletico Madrid were relegated.
Montpellier's Olivier Giroud, left, and Marco Estrada, right, celebrate after their French League one soccer match against Auxerre at the Abbe Deschamps stadium in Auxerre, central France, Sunday, May 20, 2012. Montpellier defeated Auxerre 2-1 and celebrated its first title. (AP Photo/Thibault Camus)
Montpellier
Olivier Giroud has not proven to be the forward to fire Arsenal to Premier League glory. But he was exactly that for southern French club Montpellier in 2011-12.
Before Paris Saint-Germain acquired their vast wealth, French football did throw up different shades of winners - aside from Olympique Lyon's early 2000s dominance - including Nantes and Lens.
But the 2011-12 title win for Montpellier was unexpected. While PSG were enjoying a first season under their Qatari owners, Montpellier seemed like unlikely contenders to capitalise on a season of transition.
The previous season, the club had finished 14th and as recently as the 2008-09 campaign, they were winning promotion from Ligue 2.
But it all came together in 2012 thanks to the 21 goals of Giroud and the playmaking ability of Younes Belhanda to edge PSG by three points.
Montpellier haven't been back in the Top 6 since and are mid-table again this season.
Atletico Madrid
With hindsight it isn't as big a surprise that Diego Simeone was able to lead Atletico Madrid to La Liga glory two years ago.
He has managed to build a side that has the fighting spirit to bridge the gap to the top two in Spain.
But ahead of the 2013-14 season, Barcelona and Real Madrid had won every La Liga title since Valencia came out on top in 2004 and it seemed that would be the situation for the foreseeable future due to the huge financial gap between the El Clasico sides and the rest.
Atletico had finished third in 2012-13, a full 24 points behind Barca but a side featuring goalscorer Diego Costa, the creativity of Koke, a durable defence and goalkeeper Thibaut Courtois hung in there until the final day of the following season, while also reaching that season's Champions League final in an outstanding campaign.
On the final matchday, facing Barcelona in a straight shootout for a first La Liga title in 18 years, Atleti led the league by three points and needed to avoid defeat to clinch glory.
Barca took the lead that day, but with destiny on the Madrid club's side, defensive leader Diego Godin rose to head home in the second half to secure the point Los Colchoneros needed.
It's no flash in the pan either as Atletico challenge for this year's title again and are on the verge of Champions League final participation once more.
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