What is the most common March Madness upset? Taking a look at the seeds that have been on the wrong end of NCAA tournament history

The collegiate basketball season heats up as March arrives, with big matchups in March Madness determining the path to the national title.

On Sunday, fans were treated to a run of tight games that not only provided entertainment but also offered some insight into the probable results of the forthcoming NCAA tournament.

A lot was going on that day, from dominating performances to shocking upsets, which might have an impact on the ultimate tournament seeds.

The nature of March Madness is such that unexpected victories and shocking upsets are quite common. Thanks to the format of the game, teams ate often placed in their least favorable spots as they compete for the championship.

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The unlucky 13th seed, with no championship

San Diego State v Connecticut

None of the 13 seeds have ever claimed victory in the NCAA Tournament, and it's unlikely to change for a while. Although six teams seeded No. 13 have advanced to the second weekend, none of them have progressed beyond the Sweet 16.

Throughout the 40-year expansion of the NCAA Tournament bracket, which reached 64 teams in 1985, there have been 26 different tournaments where at least one game was won by a 13 seed.

On four occasions, multiple 13 seeds emerged as winners. These instances occurred in 1987 with Xavier and Missouri State, 2001 with Indiana State and Kent State, 2008 with Siena and San Diego, and in 2018 with Buffalo and Marshall.

The upsets witnessed in 2008 were particularly noteworthy, as both victories took place on the same court in Tampa. It was an unprecedented occurrence in the history of the NCAA Tournament.

Additionally, the other two teams that triumphed that day in Tampa were also double-digit seeds. Western Kentucky, seeded 12th, secured a stunning victory with a buzzer-beater in overtime, while 12th-seeded Villanova rallied from an 18-point deficit to beat Clemson.

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The most common 5 vs 12 upsets

Since the NCAA tournament field expanded in 1985, the 12-5 upset has occurred quite a few times and has become one of the most popular March Madness picks each year

Since the NCAA tournament field expanded in 1985, there have been 53 upsets by teams ranked 12 or lower. As of 2024, the lower seed has had a win percentage of 34.87, with a 53-99 record.

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Some notable instances of 10 vs 7 in March Madness

San Diego State v Connecticut

In 2022, No. 12 Richmond took out No. 5 Iowa, while New Mexico State beat UConn. No. 10 seeds hold a 59-92 record against No. 7 seeds, equating to a 38.82 winning percentage.

In 1999, there was only one tournament where the No. 7 seeds were swept by 10s. On the flip side, there have only been two tournaments where all four No. 7 seeds advanced: 1993 and 2007.

In 2019, No. 10 seeds went 3-1 against 7s, with Florida, Iowa and Minnesota advancing as the lower seeds, while Wofford was the only No. 7 seed to win. In 2021, No. 7 Oregon's advancement past No. 10 VCU happened because of COVID-19 protocols and a no-contest designation.