PROVO, Utah (ABC4 Sports) – It has all the makings of a big-time upset at the Marriott Center Saturday night.

BYU led #22 St. Mary’s 56-55 in the final seconds, when Aidan Mahaney hit a fadeaway jumper with .4 seconds left on the clock to give the Gaels a one-point win.

Freshman Dalllin Hall led the Cougars with a career-high 23 points, while Fousseyni Traore added 11.

“Obviously this was a very tough, disappointing end to a terrific game against a great team,” said BYU head coach Mark Pope. “I thought our guys competed in every way and made big plays down the stretch. I’m really proud of our guys and congratulations to St. Mary’s.” 

This is the second time this month BYU has lost to a ranked opponent in the final seconds at home. The Cougars fell to Gonzaga by one point on January 12th on a shot with nine seconds left.

BYU played the Gaels very short-handed, after Jaxson Robinson, Noah Waterman and Atiki Ally-Atiki were all suspended for the game for violating team rules.

Logan Johnson led five Gaels in double figures with 14 points. Alex Ducas poured in 12 points, while Mitchell Saxon added 11.

BYU trailed by as many as 11 points in the first half, but rallied back with a 17-3 run to tie the game at 25 at the half.

The Gaels took a 51-43 lead with 5:30 left in the game, before Hall hit a jumper and Gideon George drilled a three-pointer to cut the deficit to two.

Spencer Johnson hit back-to-back three-pointers to give BYU a 55-53 lead with 2:18 left in the game. Logan Johnson tied the game at 55 for St. Mary’s with a bank shot with 1:53 left.

After both teams failed to score, Hall converted one of two free throws with ten seconds left, setting up Mahaney’s dramatic game-winner.

Hall made 9-of-14 shots from the field, to go along with four rebounds and two assists

“Dallin didn’t have a great week this week last week,” Pope said. “He came in on Monday and had a fire in his eyes and a determination to refuse to let that week define him. That manifested itself in many positive ways tonight. His resolve, commitment and his obsession with getting better were really spectacular. He’s carrying a lot on his shoulders and he certainly was great tonight.”

The Cougars shot 42.3 percent from the field, 33.3 percent from three and 60.0 percent from three. They out-rebounded the Gaels, 33-25, with 12 of those coming on the offensive glass. St. Mary’s shot 43.1 percent from the floor.

BYU (14-10, 4-5 WCC) has now lost three in a row, and will next host Loyola Marymount Thursday, Feb. 2. The Lions defeated the Cougars earlier this month in Los Angeles.

“It doesn’t get any easier, so we just need to get better,” Pope said. “We don’t have the luxury of feeling sorry for ourselves. We are in a little bit of a hole right now, but we are optimistic that we can keep getting better. There is a lot of season left, with everything on the table, so we just need to get better.”