Most March Madness brackets already busted

The CNBC guide to bracketology
The CNBC guide to bracketology

The Madness in March has officially begun.

Two 14-seeds, UAB and Georgia State, have already won their games early on the Thursday schedule. According to ESPN, 99.3 percent of brackets in its 11.57-million bracket competition are already busted.

Georgia State in particular was a massive surprise. According to one win probability calculator, 3-seed Baylor had a 99.9 percent chance of winning the game, considering its double digit lead with under two minutes to play. And yet, Baylor blew it—along with the brackets of millions of others along the way.

An estimate from WalletHub pegged $12 billion in gambling wagers globally on the tournament. Some lucky (or smart) UAB and Georgia State fans will be looking at big returns.

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They were two of the least likely schools to win their opening games. According to the data scientists at Kaggle, which is running a bracket competition for statistics pros, UAB only had a 13.4 percent chance of winning against Iowa State on Thursday. Georgia State was similarly positioned at 20.7 percent. And the combination of both winning was effectively zero—hence all the busted brackets.

"We could say with 90 to 95 percent confidence that at least one of the teams seeded #13 or worse was going to win their first round matchup," said Kaggle's Jeff Sonas."The best Kaggle projections were that two such upsets would happen."

"There are so many of such games in the first round that it's not a surprise when some of these upsets do happen," he added.

Georgia State upsets 3rd seated Baylor in the second round of the 2015 NCAA Men's Basketball Tournament.
Getty Images

For a bracket this year that so many people had pegged as being the best for top favorites, we are seeing the magic of the tournament play itself out.

"The 14 seed is the new 12 seed," said one analyst, referring to the mythology of 12s often beating 5s. A 14 seed has now won for three years in a row.

And we have just barely started.