Long before the end of the first round, all brackets in the CBS Sports Bracket Challenge were busted. After just one bracket in the Bracket Challenge survived the first day, the lone holdout was no longer perfect after No. 5 seed Colorado's 96-73 win over No. 12 seed Georgetown in the East Regional. With the NCAA Basketball Tournament back for the first time since 2019 -- after it was canceled due to the outbreak of the coronavirus pandemic in the United States last spring -- March has certainly brought with it the usual madness on the bracket. 

The first big domino to fall came in the South Regional where No. 15 seed Oral Roberts upset No. 2 seed Ohio State 75-72 in an absolute shocker on Friday. Just how big of a shock? Of the users on CBS Sports Bracket Challenge, 97% of them had the Buckeyes advancing past the Golden Eagles in the first round, and with good reason -- its only the ninth time, since the field expanded to 64 teams in 1985, that a No. 15 seed has knocked out a No. 2 seed. To make matters worse for some of those OSU supporters, 4% of all Bracket Challenge players had the Buckeyes winning the whole thing.

After that, the number of perfect brackets was quite low and that number continued to whittle for the rest of the day with more upsets. No. 12 seed Oregon State beat No. 5 seed Tennessee, No. 11 seed Syracuse handled No. 6 seed San Diego State in the Midwest Regional and No. 13 seed North Texas eliminated No. 4 seed Purdue in the South Regional.

March Madness has truly returned, the upsets and surprises are sure to continue in the this year's NCAA Tournament.