Odds Shark Top Sportsbooks
*Terms and Conditions apply to all bonus offers on this website. Visit operator for details.

Biggest Upsets In Sports History: Where Does Leicester City Land?

Is there any better feeling for a sports bettor than hitting an underdog? The longer the odds, the bigger the thrill! It almost feels like you beat the sportsbook and it doesn’t hurt to see your bankroll increase significantly. Sure, hitting a +200, or 2:1 underdog which, according to our sports betting calculator, has a win probability of 33.33 percent is riveting, but how about a +500000 or 5000:1 underdog?

Although a huge upset is rare, there have been some instances burned into sports fans’ minds for years and decades to come, regardless if you bet on it or not. I am going to look at some of the most memorable sports betting upsets and what their odds were below.

See Odds Shark’s Best Betting Sites

Biggest Upsets In Sports Betting History

YearTeam/PersonFeatOddsProbability
2015-16Leicester City FoxesWin Premier League+5000000.02%
2018UMBCNo. 16 beats No. 1 March Madness~+20004.76%
1990Buster DouglasKnocked out Mike Tyson+42002.33%
2004Boston Red SoxWin World Series+120000.83%
2011St. Louis CardinalsWin World Series+200000.5%
1999St. Louis RamsWin Super Bowl+300000.33%
2016Cleveland CavaliersWin NBA Title+11008.33%
2011-12Los Angeles KingsWin Stanley Cup+28003.45%
2007Appalachian StateFCS Beats Ranked FBS Team~+85001.16%
2007Matt SerraKnocks Out Georges St. Pierre+85010.53%

2015-16: Leicester City Win Premier League (+500000)

We have to start this list with the biggest upset in sports betting history, the Leicester City Foxes winning the Premier League in the 2015-16 season. Chelsea opened the season as the +160 betting favorites with Leicester not found until 13th on the oddsboard at +500000.

Diehard fans, like you, maybe sprinkle a small wager on a futures ticket in hopes your team would reach the promised land, though in this case, the payout would be that much sweeter where a simple two-dollar wager would make you 10,000 dollars richer.

How did this come to be? Well, in the 2014-15 campaign, the Foxes found themselves at the bottom of the league table at one point in the season, though a late-season surge saw them win seven of their last nine to finish 14th and somehow avoiding relegation. After this rough campaign, manager Nigel Pearson was fired and former Chelsea manager Claudio Ranieri took over.

Early in the season, Jamie Vardy was carrying the squad with 13 goals in 11 straight matches and come Christmas Day, one year from being in the basement, Leicester City was atop the Premier League table.

The odds were slow to react, though, as the Foxes were still +1750, or 175:1, 5.41 percent win probability, on January 1. The team continued to win and eventually qualified for the UEFA Champions League for the first time in franchise history.

Then, on May 2, 2016, tragedy struck the sportsbooks as Leicester City won the Premier League, cashing at 5000:1 for preseason bettors, almost 1000:1 at the start of December and even 87:1 at the start of February. Every dog has its day!

See Odds Shark’s Best Soccer Sites

2018: No. 16 UMBC vs No. 1 Virginia (~+2000)

The same thing that won the Virginia Cavaliers a national championship in 2019 is the same thing that got them in trouble in 2018. Virginia had a suffocating defense that limited opponents to just 54 points per game, the fewest in the nation which carried them to a 31-3 regular-season record, 17-1 in the ACC, an ACC tournament championship and the No. 1 seed in the national tournament.

The problem came on offense in which the Cavaliers ranked 298th with 67.1 ppg, leaving little room for error in the event the defense took a night off. UMBC was slightly better on offense with 71.6 ppg, while surrendering a respectable 69.8 ppg on defense. The Retrievers won the America East Tournament to get their record to 24-10 and earn the 16-seed into the March Madness.

Virginia opened as a 20.5-point favorite in this contest and the two squads were knotted at 21 heading into the locker rooms at half – all seems normal. However, whatever oranges were served or the pep talk UMBC head coach Ryan Odom delivered, it landed, as UMBC dominated the second half outscoring Virginia 53-33 to end the streak of 135-0 for No. 1 seeds in the NCAA Tournament.

To put in perspective the job the Retrievers did in that second half, the Cavaliers allowed fewer than 53 points in 15 full games in the regular season.

See Odds Shark’s Best NCAAB Sites

1990: Buster Douglas vs Mike Tyson (+4200)

Though the odds do seem to be a bit of a mystery for this bout, some say 42:1 some say 40:1, regardless that night of February 11, 1990, in Tokyo, is one that many boxing fans will never forget. The Baddest Man on the Planet, Tyson, at the ripe age of 23-years-old, carrying a record of 37-0 with 33 of those wins coming by knockout, which led to him to be the undisputed champion with the WBA, WBC and IBF heavyweight titles.

For Douglas, he carried a 29-4-1 record having once fought for the IBF heavyweight championship against Tony Tucker in which he was knocked out in the 10th round. This was a mismatch on paper but the personal life may have given the keen bettor an edge on the underdog.

Iron Mike had parted ways with his manager Bill Clayton and trainer Kevin Rooney, he was being divorced and battling Don King over contracts. On the other side, Buster was fighting with a heavy heart after losing his mother just three weeks prior to the biggest fight of his life.

Perhaps it was the out-of-ring pressure or the 12-inch reach advantage that Douglas had over Tyson, but a relentless jab throughout the fight leading to a flurry of punches in the 10th round sent the baddest man on the planet to the floor for the first time in his career. That was the end of the fight as a 10-second count later the belts changed hands, and underdog bettors rejoiced at their 42:1 wagers.

See Odds Shark’s Best Boxing Sites

2004: Boston Red Sox Win World Series (+12000)

People nowadays may think of the Boston Red Sox as a perennial powerhouse winning four World Series titles in the last 16 years, but prior to getting over the hump in 2004, the BoSox suffered from the Bambino Curse that saw them go on an 86-year drought after trading Babe Ruth to the rival New York Yankees in 1919.

Over that span, the Bronx Bombers collected 26 World Series titles, the most of any team in MLB and a rivalry got bitter as the Yankees had money to buy players, stacking teams, while the Red Sox were often just second fiddle. In 2004, Boston racked up 98 wins in the regular season, the third-most since trading Ruth and better yet, it won 11 of 19 games vs New York.

The two locked horns in the ALCS and once again, big brother New York asserted its dominance by going up 3-0 over the Red Sox as “Who’s your daddy” echoed through the ballparks when Pedro Martinez was on the hill following a late-season comment. At this time, with no team ever coming back from an 0-3 deficit, Boston was +12000 to win the World Series.

The Red Sox stole Game 5 in a five-hour-49-minute, 14-inning, marathon. Game 6 featured the bloody sock game with Curt Schilling pitching a gem with a torn tendon sheath in his right angle and blood was visible through the sock. Game 7 was a Red Sox beat down 10-3 to complete the comeback.

There was no stopping the Red Sox then as they swept the St. Louis Cardinals in the World Series to break the curse and cash as a 120:1 underdog. They remain the only MLB team to come back from a 3-0 deficit.

See Odds Shark’s Best MLB Sites

2011: St. Louis Cardinals Win World Series (+20000)

Was it a collapse by the Atlanta Braves or a resilient never-say-die mentality by the St. Louis Cardinals? In late August, the Cards trailed the Braves by 10.5 games in the wild-card race but Atlanta stumbled from that point forward dropping six of 13 games to set up a date with St. Louis in early September. The struggles continued for the Braves as they were swept in that three-game series, though, the Cardinals were still 4.5 games back with 16 games to go and their playoff chances were on life support at 7.7 percent.

Entering September, St. Louis had odds of +20000, but went on a tear to win 18 of its 26 games that month and on the last day of the season, the Redbirds scored an 8-0 win over the Astros while the Braves lost in extras to the Phillies, punching a playoff ticket for St. Louis. The Cards completed the largest comeback to make the playoffs in MLB history after 130 games, but more excitement loomed.

Fast-forward to the World Series against the Texas Rangers where David Freese made history for St. Louis. In Game 6, with the Cards trailing the Rangers 3-2 in the series and 7-5 in the ninth, Freese was at the dish with two on, two out and two strikes. He hit a triple to send it to extra innings. Freese then hit a walk-off home run in the 11th to force a Game 7.

In that deciding game, Texas grabbed a 2-0 lead, but that would be the only runs it scored as St. Louis scored six unanswered to win 6-2 in a remarkable comeback story.

See Odds Shark’s Best MLB Sites

1999: St. Louis Rams Win Super Bowl (+30000)

To say that expectations were low for the 1999 St. Louis Rams is an understatement as sportsbooks listed their win total at 5.5 games, ahead of only three other clubs with lower totals set. Perhaps it was the fact that the Rams went 4-12 in the previous season, finishing fifth in the NFC West and scoring the third-fewest points in the NFC. The team also had just one Pro Bowler on its roster.

The deck was even more stacked heading into the ’99 season. The Rams had signed 28-year-old QB Trent Green who was coming off his rookie season with Washington, but he suffered a season-ending injury in the preseason. In stepped future Hall of Famer, though we didn’t know it at the time, Kurt Warner. He was an undrafted signal-caller who spent three years in the Arena Football League (where he was a two-time MVP), one year in the NFL Europe League, and made 11 pass attempts in the NFL in 1998.

Well, he took the league by storm, throwing for 4,353 yards with 41 touchdowns and a 109.2 passer rating, leading the Rams to a 13-3 season where he was named league MVP and Super Bowl MVP — the books didn’t know what had hit them. It wasn’t all Warner, as there were six other Pro Bowl selections on the team; three of which became Hall-of-Famers.

St. Louis was the -250 favorite to win the Super Bowl come Conference Championship weekend and toppled the Tennessee Titans 23-16 in Super Bowl 34.

See Odds Shark’s Best NFL Sites

2016: Cleveland Cavaliers Win NBA Title (+1100)

LeBron James was in his seventh NBA Finals, but winning the title proved to be difficult as his teams had gone 2-4 over his previous six appearances. Now he was playing a record-breaking, 73-win Golden State Warriors team that looked unstoppable. The Cavs were limited to fewer than 100 points in three of the first four games, which put them into a 3-1 series deficit, a hole no team had ever dug out of, and their odds fell to +1100.

In Game 5, the Warriors were without star Draymond Green due to suspension and perhaps that was the opening the Cavs needed as James and teammate Kyrie Irving became the first duo in NBA Finals history to both score 40 or more points in the same game. James followed that performance with another 41-point showing in Game 6 en route to a 115-101 win and setting the stage for Game 7.

It was a defensive slog in that deciding game. James and Irving combined for 53 of the Cavs’ 93 points, while Green was the lone player to top 20 points for the Warriors, and in fact, he had a game-high 32 points. However, it wasn’t enough as Cleveland clamped down defensively to eke out a 93-89 victory to complete the comeback, cash as a +1100 underdog and bring the title back to Cleveland.

See Odds Shark’s Best NBA Sites

2011-12: Los Angeles Kings Win Stanley Cup (+2800)

In hockey, it’s very common to hear come playoff time that a hot goalie can win you the Stanley Cup and that is essentially what we saw in a great turnaround for the LA Kings in 2011-12.

In December, the Kings fired head coach Terry Murray and hired no-BS head coach Darryl Sutter, who coached his teams to the playoffs in 10 of his previous 11 seasons, including the Calgary Flames' Stanley Cup run in 2003-04. The Kings went on a tear when he was first hired, but then returned to their same-old losing ways in the new year.

Heading into the last month of play, the Kings were 10th in the West and +2800 to win the Stanley Cup, but a 12-4-3 run secured the eighth and final playoff spot. From the start of March through the end of the playoffs, the Kings gave up more than two goals in just eight of their final 35 games.

Goaltender Jonathan Quick won the Conn Smythe Trophy as Stanley Cup Playoff MVP and the Kings became the first-ever eight seed to win a North American championship.

See Odds Shark’s Best NHL Sites

2007: Appalachian State Mountaineers vs No. 5 Michigan Wolverines (~+8500)

Although the moneyline was off the board in many places for this game, No. 5 Michigan was a 33-point favorite over FCS-side Appalachian State at the big house, which comes out to about +8500 if a moneyline was available. Perhaps the Mountaineers found a book where they could make that wager and took some of the $400,000 they were paid to come and play the Wolverines on Sept. 1, 2007.

App St. carried a 28-17 lead into halftime on the heels of a 21-point second quarter and QB Armanti Edwards had four total touchdowns (three through the air, one rushing). It all came down to defense in the second half to hang on and that’s exactly what happened.

The Mountaineers only mustered six points on two field goals in the second half while the Wolverines narrowed the gap with 15 points. App State hit a 24-yard FG with 26 seconds to go to take a 34-32 lead. Michigan QB Chad Henne got the ball with 15 seconds left on its own 34.

He hit Mario Manningham for 46 yards putting the Wolverines in field goal range. A 37-yard attempt with no time on the clock was blocked and the Mountaineers completed the stunning upset becoming the first FCS team to beat a ranked FBS team.

See Odds Shark’s Best NCAAF Sites

2007: Matt Serra vs Georges St. Pierre (+850)

You can’t have the greatest of all-time argument in the UFC without mentioning Georges “Rush” St. Pierre and many who have competed in the sport have him ranked No. 1. However, if you look at GSP’s record, he has two losses with the first coming against Matt Hughes when he was a +225 underdog. GSP would later avenge this defeat to win the welterweight title.

St. Pierre's first title defense came against "The Ultimate Fighter" Season 4 winner, Matt “The Terror” Serra. GSP was a -1300 favorite in this fight with Serra coming back as a +850 underdog.

Serra, a shorter, stocky guy with really good Jiu-Jitsu skills, threw an overhand right that clipped St. Pierre behind the ear, knocking off his equilibrium. The Terror then rushes him with a flurry of punches to win the title via first-round knockout and pull off on of the biggest upsets in UFC history.

See Odds Shark’s Best UFC Sites

When it comes to placing your futures bets, don't forget to take a look at the underdogs. As you can see from the heroic tales listed here, there are no guarantees in the world of sports and there's nothing quite like cashing a huge bet on a long-shot.