Trey Burke was clutch for the Wolverines on Friday. Reuters

The NCAA Tournament is down to eight teams, as Friday night's games only produced one surprise.

In the South Region, No. 4 seed Michigan defeated No. 1 Kansas in overtime, 87-85. The Wolverines trailed the Jayhawks by 14 points with less than seven minutes left, and also by five with 21 seconds left, but Trey Burke helped spark the comeback. The sophomore guard finished with 23 points and dished out 10 assists.

Up next for the Wolverines are the Florida Gators, who managed to avoid an upset to No. 15 seed Florida Gulf Coast, 62-50. Florida struggled in the first 12 minutes, but went on a run to end the first half, and never surrendered their lead in the second half. Gators guard Mike Rosario led all scorers with 14 points.

The Eagles committed 20 turnovers, while the Gators turned the ball over just 10 times.

In the Midwest Region, the Louisville Cardinals became the only No. 1 seeded team in the tournament following their victory over the Oregon Ducks, 77-69. Louisville shot 53.8 percent from the field, and were led by guard Russ Smith who scored 31 points. The junior hit 12 of his 14 free throws.

The Ducks' loss means no Pac-12 team advanced beyond the Sweet 16.

In the showcase game, No. 2 Duke defeated No. 3 Michigan State, 71-61. The Blue Devils were excellent from the free-throw line, hitting 24 of their 26 attempts. Senior guard Seth Curry led all scorers with 29 points.

The Spartans cut the Blue Devils' lead to five points midway through the first half, but were never able to get any closer, as Rasheed Sulaimon hit two layups and seven free throws to help Duke earn a matchup with Louisville.