Every sport produces, eventually, a night that nobody priced correctly. The line was set, the line was wrong, and the world had to file new mental paperwork. Here is the biggest single-game upset in each major sport, translated into what a dollar would have returned at the pre-game number. All payouts are approximate and based on widely-reported lines from the time.
Boxing, Buster Douglas KO Mike Tyson, Tokyo, 1990
Tyson was 37-0. Douglas was a club fighter pulled out of obscurity. Multiple US books opened the fight at 42-1 against Douglas; the Mirage in Vegas was reportedly the only place that bothered hanging a line. Douglas knocked Tyson down in round ten. A dollar paid roughly $43. It is the oldest, cleanest reference point in the entire upset canon.
Horse racing, Mine That Bird, 2009 Kentucky Derby
A 50-1 morning-line gelding from New Mexico, hauled to Churchill Downs in a borrowed trailer, came up the rail under Calvin Borel and won the Derby by six and three-quarter lengths. A $1 win ticket paid about $51. The footage of the call is one of the most disoriented broadcasts in racing history because the announcer simply does not believe what he is seeing.
Tennis, Roberta Vinci d. Serena Williams, 2015 US Open SF
Serena was three matches from a calendar Grand Slam. Vinci was a 33-year-old doubles specialist who had reportedly booked her flight home before the match. Some offshore books listed Vinci as long as 300-1 in pre-tournament outright markets; the match-line itself was a more modest blowout favorite for Serena. Vinci won in three sets and immediately apologized to America in her on-court interview.
College football, Appalachian State 34, Michigan 32 (2007)
Michigan was preseason top-five. App State was an FCS program nobody outside Boone, NC had heard of. The point spread was around 33 points; the moneyline was reportedly in the +1500 to +2000 range depending on the book. App State blocked the game-winning field goal as time expired. A dollar would have paid somewhere around $16-21.
College basketball, UMBC 74, Virginia 54 (2018)
Virginia was the No. 1 overall seed. UMBC was a 16. No 16 had ever beaten a 1 in the men's NCAA tournament. Lines varied, but moneyline reports for UMBC sat in the +2000 to +2500 area. UMBC won by twenty. The bracket pool that year was, statistically, the worst-performing March of the modern era, because everyone had Virginia.
Soccer, Saudi Arabia 2, Argentina 1 (2022 World Cup group stage)
Argentina were heavy favorites and on a 36-match unbeaten run. Saudi Arabia were +1400 to +1600 outright depending on the book. They won 2-1 in Lusail. A dollar paid around $15-17. Argentina then went on to win the entire World Cup, which somehow makes the result both worse and funnier in retrospect.
MMA, Holly Holm KO Ronda Rousey, UFC 193 (2015)
Rousey was the biggest star in the sport and a -800 to -1100 favorite depending on where you looked. Holm was reported around +700 to +900. Holm head-kicked Rousey in round two and the cultural pillar of UFC women's bantamweight folded on the spot. A dollar on Holm paid somewhere around $8-10.
The sports without one clean answer
NBA and NHL single-game upsets are harder to canonize because regular-season lines move daily and the playoff format is series-based. The biggest NBA shocks tend to be best remembered as series, 8-over-1 first-round wins, blown 3-0 leads in conference finals, rather than one specific evening with a famous moneyline. Same in hockey, where the Miracle on Ice still owns the genre and nothing single-game has touched it since.
Frequently asked questions
Are all the odds on this page exact?
No, they're approximate, drawn from the most widely-cited reported lines from the time of each event. Pre-game lines varied across books and not every market is well-archived. Treat the dollar payouts as illustrative.
Why are some sports missing?
Some sports, especially NBA basketball and NHL hockey, don't produce a single canonical biggest-upset game the way boxing or college football do. Their famous chaos tends to live across multi-game series, not one night.
What's the biggest single-game upset of the modern era?
By moneyline, Buster Douglas over Tyson is still the cleanest. By sport-shaping cultural impact, Appalachian State over Michigan is right there. By sheer 'where were you' reaction, Saudi Arabia over Argentina.
Do single-game upsets like these ever repeat?
Truly extreme moneyline upsets are rare by definition, they require the favorite to be a near-lock and the underdog to be near-dismissed. A few connect every year across all global sports combined.