Jared Terrell had 17 points to help the Rams (22-5, 15-1) win for the 19th time in 20 games. It was their third straight after their school-record 16-game winning streak was halted by St. Bonaventure last Friday night.
In 1980-81, the Rams tied Duquesne for a share of the conference title, their only other regular-season A-10 championship.
When the game ended, blue and white confetti - the school colors - and streamers fell from the ceiling. Terrell climbed the scorer's table, waving to the crowd.
Coach Dan Hurley said to the crowd over a microphone: "Let's bring down this net baby, what do you say?"
Jalen Crutcher led the Flyers (13-15, 7-9) with 12 points.
Playing for their first conference regular-season title in school history already had the sellout crowd fired up, but it picked up to a notch at the end of 7-0 spurt early in second half when Hurley walked onto the floor, waving for more noise when Dayton called timeout after the Rams went up 46-38 with 16:08 to play.
Following the timeout, URI continued its stifling, man-to-man defensive pressure and took charge with an 11-4 spurt that was capped by Matthews' 3-pointer from the left wing that pushed its lead to 15 with 13:17 to play. The Rams had two easy breakaway baskets off turnovers in the spree.
They pushed it to 72-46 on Dowtin's 3 with just over five minutes to play, sending Hurley to the floor again waving after another timeout.
In the opening half, the Flyers shot 58.3 percent and led most of the way despite nearly hitting their per-game average with 13 turnovers before URI closed by scoring nine of the final 11 points to take a 36-34 edge into intermission.
The Rams entered the game as one of the best in the nation, creating 16.38 turnovers per game. Dayton came in committing just 13.6 per, but finished with 22.
HOME SWEET HOME
The Rams improved to 15-0 in the raucous Ryan Center, tying the school-record for most home wins in a season. They also did it in 1987-88 when the program advanced to the Sweet Sixteen in the NCAA tourney.
Dayton fell to 1-9 on the road this season.
Dayton: The Flyers were hoping to spoil the party by winning their third straight game to reach .500 in league play.
Rhode Island: The Rams are certainly playing the rest of the regular season and conference tourney, looking for a better seed in a probable selection to NCAA Tournament - even if they don't win the postseason A-10 tournament.
Dayton: At La Salle on Wednesday night in its final road game of the season.
Rhode Island: Hosts Saint Joseph's on Tuesday night in its final home game.
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