U.S. college basketball's Bucknell Bison and Vermont Catamounts have pulled of the two biggest upsets so far in this year's national championship tournament.

Fourteenth-seeded Bucknell surprised third seed Kansas, 64-63, knocking the Jayhawks out in the first round. Bucknell's Chris McNaughton scored on a layup with 10 seconds remaining for a one-point lead, and Kansas missed what would have been a winning basket just before the buzzer, sending the Bison into the second round. Bucknell started playing basketball in 1896, but had never won a tournament game until Friday.

In an earlier contest, 13th-seeded Vermont hit two straight three-point shots in overtime to upset fourth seed Syracuse, 60-57. The first-round loss by the Orangemen Friday came just two years after they won the national title.

Another notable upset in Friday's 16 first-round games was a 75-63 win by North Carolina State, a 10th seed, over Charlotte, their cross-state rivals, a seventh seed.

Regional top seeds Duke and North Carolina both advanced, although the Blue Devils struggled early with 16th seed Delaware State before Duke earned a 57-46 victory. The North Carolina Tar Heels routed Oakland, Michigan 96-68.

In other contests from the four regions Friday, second seeds Oklahoma State and Connecticut were victorious. The OSU Cowboys downed Southeastern Louisiana, 63-50, while the defending national champion U-Conn Huskies got by Central Florida, 77-71.

Fourth seeds Louisville and Florida earned hard-fought victories. The Louisville Cardinals struggled to beat Louisiana-Lafayette, 68-62. The Florida Gators blew a 20-point lead late in the game but held off Ohio, 67-62.

Fifth seeds Michigan State, Villanova and Georgia Tech, winners all, will play their second-round games on Sunday. The MSU Spartans downed Old Dominion, 89-81. The Villanova Wildcats beat New Mexico, 55-47. And the Georgia Tech Yellow Jackets used a late run to hold off George Washington, 80-68.

The sixth-seeded Wisconsin Badgers struggled before defeating Northern Iowa, 57-52. Seventh seed Southern Illinois hit free throws late in the game to break a tie and defeat St. Mary's (of California), 65-56. Both ninth seeds in action Friday picked off number-eight seeds -- Iowa State beating Minnesota, 64-53, and Mississippi State crushing Stanford, 93-70.

The single-elimination field will be cut to 24 teams Saturday with eight second-round games. The surprising Wisconsin-Milwaukee Panthers and Alabama-Birmingham Blazers have a chance to reach the NCAA tournament's "sweet 16," but will need to pull off their second straight major upsets. Twelfth seed Milwaukee meets fourth seed Boston College, while 11th seed Birmingham faces third seed Arizona.

Tournament play continues through April 4, when the national champion will be crowned in St. Louis, Missouri.