Another strong finish by Tu Holloway put 25th-ranked Xavier on the threshold of another championship.
Holloway scored 26 points and hit Xavier's most important shots in the closing minutes Sunday, setting up a 66-62 win over Dayton that kept the Musketeers alone in first place in the Atlantic 10.
Two more wins and they'll have a fifth straight regular-season title. Holloway played the main role in getting them there on Sunday.
"You've got to be a fool to not put the ball in his hands down the stretch," coach Chris Mack said.
Xavier (22-6, 13-1) retained its one-game lead over Temple heading into the final week of the regular season. The Musketeers have won at least a share of the last four A-10 season titles, finishing tied with Temple last year.
The Musketeers can clinch the title outright by beating Charlotte at home and winning at Saint Louis. Their only conference loss came at Charlotte, 66-62 on Feb. 2. The Musketeers have won seven in a row and 14 of their last 15 overall.
Temple finishes at Massachusetts and at home against La Salle.
Dayton (19-10, 7-7) trailed by 11 before a late comeback tied it at 59 with 1:41 to go. The Flyers tried to keep the ball out of Holloway's hands, but couldn't do it.
Holloway was fouled and made two free throws, then hit a 3-pointer with 41 seconds left for a 64-59 advantage. He scored 16 of Xavier's final 24 points.
Jamel McLean added 11 points and Mark Lyons 10 for Xavier. Chris Johnson had 22 points for Dayton.
The victory completed a two-game series sweep for Xavier, which has dominated Dayton lately. The Musketeers have won 11 of the last 13 games between the southwest Ohio private schools, separated by an hour's drive. The Flyers' two wins during that stretch came at UD Arena the last two seasons.
"I really believe that over the last couple years, we came out here and got embarrassed," Holloway said. "We were saying, 'We're not going to make it like the last two years where those guys jumped out on us.' We wanted to be the ones that jumped out on them."
Dayton's only good moments came at the start. Johnson opened the game with a pair of 3s for a 6-2 lead, but Xavier went on a 12-2 run and never trailed again. The Musketeers led by as many as 13 in the first half, taking a 37-25 lead into halftime.
Xavier held on until Dayton's late run tied it and Holloway took over. His two free throws put the Musketeers ahead to stay, and his 3-pointer put them in control. He had two more free throws in the closing seconds to wrap it up.
"He's really elevated himself from last year," Mack said. "He was a good player a year ago. He's a phenomenal player today. In my opinion, and I know I'm not really objective, he's the best player in our conference. And I think his play and our play as a team is reflective of that."