Talk about a rough day for one big bettor.

Biloxi’s Beau Rivage casino took a $344,126 bet Saturday on the college basketball tournament often branded as March Madness. The better was hoping to win more than $800,000 by correctly picking the results of two games.

One gambling industry executive said the bet was one of the largest placed so far on the tournament.

The first pick on the Beau Rivage ticket was on Missouri to be beat Princeton by at least seven points. Princeton was an underdog in the tournament, and had scored a huge upset over Arizona on Thursday to gain the right to play Saturday.

Princeton scored yet another upset Saturday, beating Missouri 78-63.

That meant the ticket’s second pick, Alabama to beat Maryland, didn’t matter anymore, as the bettor needed to get both picks correct to cash the ticket.

Princeton, from the Ivy League, is far from a traditional basketball powerhouse, so the school’s advancement to the third round of the tournament caught many by surprise.

Said one person on Twitter: “Princeton made Beau Rivage a ton of money.”