OMAHA, Neb. -- Pop Isaacs helped unranked Creighton upset No. 1 Kansas 76-63 on Wednesday night, scoring a season-high 27 points and matching his career high with six 3-pointers.
Kansas cut a 13-point deficit to one early in the second half, but Isaacs hit back-to-back 3s to rebuild the lead as the Bluejays (6-3) pulled away for their second win over a top-ranked opponent. They knocked off Connecticut 85-66 in Omaha in February.
The Jayhawks (7-1) lost a regular-season game against an unranked nonconference opponent for the first time in three years. Creighton had been in 16 straight Associated Press polls before dropping out this week after losses in three of its previous four games.
Students rushed the court at the final buzzer as flames shot up behind each backboard.
Isaacs' shooting display overshadowed what was supposed to be the featured matchup between two of the nation's best big men, 7-foot-1 Ryan Kalkbrenner and the Jayhawks' 7-2 Hunter Dickinson.
Isaacs was 10-of-15 from the field, including 6-of-9 on 3s, and added seven rebounds and four assists in his best performance since he transferred from Texas Tech in the offseason.
Kalkbrenner, who had sat out the Bluejays' previous game because of a lower-body injury, and Steven Ashworth, still feeling the effects of an ankle sprain from two weeks ago, each scored 17 points.
The Jayhawks struggled offensively and never led. Dajuan Harris had 15 points and AJ Storr and Zeke Mayo added 12 apiece for Kansas, which shot 36% from the field.
The game marked Kansas' 105th game against an unranked opponent as the AP No. 1 team. Only two other times before Wednesday had the Jayhawks lost by double digits in such cases.
Information from ESPN Research and The Associated Press was used in this report.