Las Vegas • BYU’s 85-72 win over No. 20 Saint Mary’s in a West Coast Conference semifinal game Monday night was a year in the making.

After getting blown out by 31 points by the Gaels 364 days ago in the same conference tournament game at Orleans Arena, the Cougars began plotting their revenge. They spent hours in the summer working on ways to beat Saint Mary’s and control WCC Player of the Year Jock Landale, and the extra work paid off.

“This was a really satisfying win, especially for our guys who returned from last year,” BYU coach Dave Rose said. “Because last year was kinda tough.”

Yoeli Childs scored a career-high 33 points and outplayed the foul-plagued Landale from start to finish, while Elijah Bryant chipped in 25. But every Cougar contributed mightily, as BYU snapped a five-game losing skid against Saint Mary’s and advanced to the WCC championship game for the first time since 2015.

BYU (24-9) will meet No. 6 Gonzaga at 7 p.m. MST Tuesday night needing to win to get the league’s automatic bid to the NCAA Tournament.

“The bottom line is we feel like we are built to win this tournament. We feel like we are built to play three games in four days and [could] be able to win them all,” Rose said. “The biggest thing was to get the guys to believe in that.”

So far, so good.

“We’ve been waiting for this opportunity for a long time,” said sixth man Dalton Nixon, who scored 10 points in 23 minutes and drew two big fouls on Landale with drives to the basket.

Landale finished with 23 points on 9-of-13 shooting before fouling out with 21 seconds remaining.

“Jock scored 23 points …. and we’re all saying we handled him,” Rose said with a laugh.

Jordan Ford led the Gaels (28-5) with 27 and now Saint Mary’s must sweat out the NCAA selection show Sunday. Most bracketologists had SMC as a No. 9 seed before the loss.

The Cougars shot 61 percent from the field and were 14 of 16 from the free-throw line.

“I think it is huge just to make the right plays, and that’s what we did tonight,” said Childs, who was 3 for 3 from the 3-point line and finished 13 of 18 from the floor. “The ball was popping around and nobody was caring about what [they] were doing offensively. … The most important thing was getting the win.”

The Gaels dared Childs to beat them from mid-range and deep, and he did just that.

“I put a lot of work into my outside game over the summer,” said Childs who was 0 for 2 from distance in Saturday’s 85-79 win over San Diego. “And the coaches trusted me to keep shooting them.”

The Cougars played one of their best halves all season in the first half and took a 41-37 lead at the break when Childs hit a 3-pointer just before the buzzer. He had 18 in the first half, while Landale had just six in the first 20 minutes.

It was the second-most points the Gaels have given up in a first half this season.

Nixon drew Landale’s third foul with 1:45 remaining in the first half with a 3-point play.

TJ Haws added 11 points and seven assists and McKay Cannon came up with two of BYU’s seven steals.

With Bryant scoring five quick points, the Cougars rolled out to an 11-4 lead, but couldn’t hold it.

Saint Mary’s went on an 11-2 run, fueled by a pair of Calvin Hermanson 3-pointers, and eventually led 29-25 when Ford made his second 3-pointer. Hermanson had 12 points before fouling out.

The Cougars ended the half on a 10-2 run and were feeling good about themselves heading to the locker room at halftime, considering a year ago SMC led 36-20 at the break.

They continued the strong play into the second half, and led 63-54 with 9:40 left when Nixon made another three-point play. Nixon’s ninth and 10th points, a dunk after Cannon’s big steal, gave the Cougars a 69-57 lead with less than six minutes to play and SMC would get no closer than eight the rest of the way.

“Our guys, they kind of summed it up. They were on it,” Rose said. “We shared the ball, we played hard, we played together, we executed well, made big shots. That’s how you win.”

And how you get revenge — a year later.

BYU 85, Saint Mary’s 72

• Yoeli Childs scores a career-high 33 points and Elijah Bryant adds 25 as the Cougars advance to the WCC championship game with an upset of No. 20 Saint Mary’s

• The Cougars shoot 61 percent from the floor and avenge an 81-50 loss to SMC in last year’s semifinal game

• SMC’s Jock Landale scores 23 points but battles foul trouble and plays just 34 minutes before fouling out