Duquesne (15-7, 6-3 A-10) shot 81 percent (17-of-21) in the first half en route to a 45-30 halftime lead and their first victory over a ranked team since beating Xavier in January 1997 -- a span of 24 games against top-25 opponents.
Aaron Jackson had 21 points for the Dukes, who have won three of their last four games. Melquan Bolding had 12 points and seven rebounds.
B.J. Raymond had 11 of his 18 points in the second half for Xavier (20-3, 8-1), which had its 11-game win streak snapped. Terrell Holloway added 16 points for the Musketeers.