No. 21 UConn made just 16 baskets on 54 shots Sunday, and lost for the first time in five games.
Nick Russell and Nic Moore each scored 15 points to lead SMU (22-6, 11-4 American Athletic Conference) to the 64-55 win and a sweep of the season series with the Huskies. Markus Kennedy had 13 points and seven rebounds for SMU, which has won 11 of its last 13 games.
"We outrebounded them, but you can't shoot 29 percent," UConn coach Kevin Ollie said. "I look at my starters...it was a lot of missed shots.
The Huskies (21-6, 9-5), who came in shooting better than 46 percent, were led by their guard tandem of Shabazz Napier and Ryan Boatright, who each scored 15 points. But they combined to shoot 8 for 28. DeAndre Daniels, who had been averaging better than 13 points a game, was 2 of 10 from the floor.
"They are a terrific defensive team," Boatright said. "You can't beat them off the first option. You've got to go to the second or third options."
UConn never led. They trailed by two at halftime and by 10 points midway through the second half.
The Huskies cut the lead to 55-49 on a 3-pointer by Napier, but Sterling Brown answered with a 3-pointer and SMU held on down the stretch.
"To beat a team like SMU, you can't play in spurts," Ollie said. "And I thought we played in spurts."
Neither team could find the basket early. The first points came more than four minutes into the game on a layup by Kennedy. The teams were a combined 0 for 7 with eight turnovers before that.
It was 7-0 when before Philip Nolan gave UConn its first points on a layup more than six minutes into the contest.
Kennedy had eight first-half points and the Mustangs. But SMU never led by more than seven and UConn tied the game at 25 with under a minute to play. SMU took the lead back on a pair of Kennedy free throws, and scored the first two baskets of the second half.
The Mustangs extended the lead to 44-34, holding the Huskies without a field goal for eight minutes between two of Napier's layups.
SMU, which is seeking its first berth to the NCAA Tournament since 1993, beat UConn 74-65 in Dallas in January. The Mustangs also have wins over No. 22 Memphis and No. 7 Cincinnati in conference play. They fell out of the Top 25 after losing last week at Temple.
"We're still up and down," Moore said. "But once we get to that clicking point and we just stay at a high, I feel we can make a big run if we make the NCAA tournament."
The Mustangs already have more wins this season than any SMU team since the 1999-00. They improved to 4-4 in league play on the road and are 7-0 at home.
UConn honored its first of its three men's national championship teams at halftime, putting a plaque on its "Wall of Honor" for the 1999 champs. Khalid El-Amin, the point guard on that team, also was honored with an individual plaque.
UConn hit 6 of 21 shots from 3-point range, but has 194 on the season, three more than the Huskies had all of last season.
It doesn't get much easier for SMU, which faces Central Florida next, but still has games left with No. 11 Louisville and at No. 22 Memphis before the American tournament.
Connecticut also faces two ranked teams in its final three regular-season games, hosting No. 7 Cincinnati next Saturday and closing the season at Louisville.