There were smiles all around on the faces of Saint Mary’s players in the locker room at Orleans Arena on Tuesday night. The 21st-ranked Gaels had just beaten No. 17 Gonzaga 69-60 to pair their West Coast Conference tournament title with the regular-season crown.

Junior point guard Augustas Marciulionis recalled a less joyous postgame atmosphere back on Dec. 1, when Saint Mary’s lost by 17 points to Boise State at Idaho Falls, Idaho. The Gaels were 3-5 at that point, and there was no clear view ahead to what they achieved in Las Vegas.

“It means a lot. To win with this group of guys when we had some struggles early in the season, it’s an amazing thing,” Marciulionis said. “It makes it even sweeter, just the fact that we remember that locker room early in the year and how it is now.”The win over Gonzaga clinched a 10th NCAA tournament bid in 20 years for the Gaels (26-7), who won 23 of their past 25 games. Coach Randy Bennett said the problem early was the Gaels’ good players weren’t good enough yet to handle the team’s challenging schedule.

That included sophomore guard Aidan Mahaney, still adjusting to being No. 1 on the opponent’s scouting report. And senior guard Alex Ducas, not yet fully back after a back injury late last season. And sophomore forward Joshua Jefferson, a first-year starter.

Topping the list of players growing into new roles was Marciulionis, the son of Hall of Famer Sarunas Marciulionis, the Lithuanian star who made his NBA bones with the Warriors.

After playing just 15 minutes per game last year, Augustas was producing 8.8 points, 2.6 assists and shooting 21 percent from the 3-point arc through eight games this season.

In the 25 games since, Marciulionis gave the Gaels 13.6 points and 6.1 assists while making 40 percent of his 3’s.

Those numbers, coupled with his work on defense, made Marciulionis the WCC Player of the Year and the tournament’s Most Outstanding Player — the first Saint Mary’s player to sweep both awards since Matthew Dellavedova in 2012.

“The coaches trusted me, the players trusted me and I kind of grew into that role,” Marciulionis said. “But it wasn’t only me. There were a lot of guys who made those jumps.”

No doubt, but Bennett said Marciulionis’ improvement was startling.

“I don’t know if I’ve ever seen a bigger jump in one year,” Bennett said. “The first half of the season he wasn’t that good a player. The second half of (last) season he was helping us win games. I still didn’t see it coming.”

“He’s terrific. He’s a smart player, makes plays,” Gonzaga coach Mark Few said after Marciulionis had 13 points, eight assists, two steals, two blocked shots and no turnovers over 40 minutes in the biggest game of his life.

Ducas said in an era when players bail out so quickly when things aren’t perfect, it would have been easy for Marciulionis to transfer. The key to his emergence was simply “realizing how good he is,” Ducas said.

“He’s a huge piece of our team. I’m super-happy for him,” said Mahaney, a two-time All-WCC selection and the Gaels’ top scorer. “Last year probably wasn’t his fairytale year by any means. To know what he went through and see where he’s at now, nothing but love and respect for him.”