Duke hit 38.5 percent (10-of-26) of its three-point attempts, but Nick Collison dominated inside with a career-high 33 points and 19 rebounds.
Coming out of halftime tied at 35-all, Duke (26-7) opened the second half on a 9-1 run, including a basket by Shelden Williams and a three-pointer by Dahntay Jones.
KU (28-7) then took a one-point lead with a 9-0 run as the teams battled back and forth until midway through the second half.
Kirk Hinrich tied the game at 49-all at the 12:26 mark, and the Blue Devils hit just one field goal in the next nine and a half minutes as the Jayhawks gained control.
Keith Langford has 13 points and eight boards for KU, Aaron Miles had six points, Jeff Graves added six points and seven rebounds.
Michael Lee added five points and four boards, Bryant Nash had four points and Hinrich finished with just two points on 1-of-9 shooting.
Jones led Duke with 23 points, including 4-of-7 shooting from three-point range, and seven rebounds. Daniel Ewing added 13 points, and Chris Duhon had 12 points and six boards.
J.J. Redick and Casey Sanders each scored five points, Williams had four points, and Sean Dockery hit a three-pointer.
KU shot 43.3 percent (29-of-67) from the field, 8.3 percent (1-of-12) from beyond the three-point arc, and 58.8 percent (10-of-17) from the foul line. Duke hit 38.5 percent (25-of-64) of its field-goal attempts and 62.5 percent (5-of-8) of its free-throw attempts. The Jayhawks outrebounded the Blue Devils, 47-33.
The Jayhawks will face Arizona at 6:05 p.m. Saturday in the Elite Eight. The Wildcats defeated the Jayhawks, 91-74, earlier this season in Allen Fieldhouse.
HALFTIME REPORT
Roy Williams’ worst fear has come true — it’s raining three-pointers on the Jayhawks.
Duke hit 7-of-12 three-point attempts in the first half and led by as many as nine points, but KU took the lead with a 6-0 run late in the half before the teams battled to a 35-all tie.
Nick Collison leads KU with 12 points, Keith Langford has 10, and Michael Lee has four. Jeff Graves also has four points, but sat on the bench for much of the first half after picking up three fouls in the first 10 minutes. Aaron Miles has a three-pointer for KU, and Bryant Nash has two points.
Daniel Ewing, JJ Redick, Chris Duhon, Sean Dockery and Dahntay Jones each hit at least one three-pointer for Duke.
Ewing leads the Blue Devils with 11 points, Jones has eight, and Duhon has five. Redick, Dockery and Casey Sanders each have three points, and Shelden Williams has two points.
Kansas shot 15-of-35 from the field, 4-of-5 from the foul line and 1-of-6 from three-point range. Duke shot 13-of-28 from the floor and hit 2 of 4 free-throw attempts. The Jayhawks outrebounded the Blue Devils, 21-14.
