The biggest upset in recorded sports history is about to happen

Leicester's Marc Albrighton, center right, celebrates with team mates after scoring against Swansea during the English Premier League soccer match between Leicester City and Swansea City at the King Power Stadium in Leicester, England, Sunday, April 24, 2016. (AP Photo/Rui Vieira)

Leicester City started the Premier League season as a 5000-1 underdog to win the Premier League. With only three games remaining, the Foxes are still top of the league with a seven-point lead. Only 270 minutes away, Leicester City is on the verge of completing the biggest upset in recorded sports history.

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Earlier in 2016, the Los Angeles Lakers stunned the Golden State Warriors, a team that went on to set the single-season record for wins in the NBA. According to ESPN Stats and Info, the Lakers entered that game as the largest NBA home underdog in 20 years and recorded the largest outright NBA upset in the past 20 years. A bet on L.A. to win on the moneyline paid off 19-1 in Las Vegas, which provided a fair bit of coin for the lucky winners.

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At 5000-1, though, Leicester City winning the title is over 250 times more unlikely than the Lakers beating the Warriors, which explains why just about any and every football fan has lost his mind watching the Foxes flirt with the impossible this season.

In baseball, a St. Louis Cardinals fan bet $250 on his team winning the World Series when the team was five games out of a wildcard spot with only 15 games remaining in the 2011 season. That reckless bet, which eventually paid off, provided the lucky bettor a 999-1 payoff. Again, it bears repeating: Leicester City started the season as a 5000-1 underdog: A $1 bet will pay out $5,000.

This isn't meant to happen. But it's happening.

Why did Leicester City start the season at 5000-1 odds to win the Premier League? After improbably avoiding relegation a season ago, the Foxes started as the team most likely to be relegated and manager Claudio Ranieri began the campaign as the bookies’ favorite to get sacked. Winning the league looked like a sucker’s bet, but for the few brave souls that even put down a bit a single bank note of any denomination, it’s looking like the best bet of all time.

To provide further perspective, Holly Holm’s shocking knockout of Ronda Rousey in the UFC only paid out 8-1. In tennis, Roberta Vinci’s stunning U.S. Open upset of Serena Williams to deny the calendar-year grand slam in tennis only paid out 12-1. Combine those upsets together, and it still doesn’t come close to sniffing how improbable and fascinating Leicester’s Cinderella run has been.

Of course, no fairytale is complete without a happy ending. Leicester can clinch the Premier League title against Manchester United on Sunday with a victory at Old Trafford. If the Foxes don't finish the job, they face struggling Everton at home and then play their final game of the season at Stamford Bridge against Chelsea.

Having last season's Premier League champion be the host for Leicester City’s victory party would be poetic. Ranieri managed Chelsea when Russian billionaire Roman Abramovich took over the club, and one of Abramovich’s first notable actions was to fire Raneiri and bring in Jose Mourinho. Last December, Raneiri and Leicester City beat Mourinho and Chelsea 2-1 at the King Power Stadium in a victory that proved to be Mourinho’s final match in charge of the Blues.

Leicester City is not supposed to win the Premier League, but with only 270 minutes remaining in the season, the reality is that the Foxes are writing the final chapters of one of the greatest and most improbable sports fairytales ever told.

Shahan Ahmed is a soccer columnist for Yahoo Sports. Follow Shahan on Twitter: @ShahanLA and @perfectpass

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