Tournament Challenge: Just 66 perfect

Through 20 games of the second round, there are now just 66 perfect brackets out of the 11 million in Tournament Challenge. Also, there no more imperfect brackets, but there are still four out there with just one game correct.

Mercer and Stanford both really cut down that number Friday with their upsets.

Just 3.3 percent of brackets took 14-seed Mercer over 3-seed Duke, the lowest number among the 14-seeds. Also, 2,982 brackets have Mercer winning it all.

Meanwhile, 20.9 percent of brackets had Duke in the Final Four, with 5.3 percent of them winning the national championship. And for a little historical perspective, 1.2 percent of brackets had Lehigh knocking off Duke in 2012 when the Blue Devils were a 2-seed.

As for 10-seed Stanford, 38 percent of brackets picked the Cardinal over 7-seed New Mexico. However, that game knocked down the number of perfect brackets from 1,987 to 67. Plus, the totally imperfect brackets were done after that.

Finally, the Arizona win over Weber State knocked out one more perfect bracket.