The headlines Tuesday morning were clear: Something surprising had happened in college basketball the previous night.
North Carolina was 19-2, unbeaten in the A.C.C., and had won 12 games in a row. Louisville had four losses and was not considered top 10 material. But Louisville won.
It has been a year of upsets among the top teams in men’s college basketball. After a season in which Kentucky was unbeaten in the regular season and several other top teams had three losses or fewer, every team in this year’s current top five has from two to four losses, with difficult conference games still to play.