Andrea Hoover’s 3-pointer broke a 36-36 tie in the second half and started the Flyers (20-1, 8-0 Atlantic 10 Conference) on a 21-7 run that was capped by MacKay’s 3-pointer for a 57-43 lead with 10:04 remaining.
The Musketeers (7-15, 1-7) shot 57.1 percent (16 of 28) in the second half to stay within range, but a 3-pointer by Hoover with 46 seconds left increased Dayton’s lead to nine, 77-68.
Briana Glover scored all 13 of her points for Xavier in the second half, and Amber Gray led the Musketeers with 21 overall.
Four Dayton players joined MacKay in double-figures scoring, with Amber Deane getting 12 and Ally Malott, Kelley Austria and Olivia Applewhite each getting 11. Applewhite also grabbed nine rebounds.