UNCASVILLE, Connecticut — A’ja Wilson sprayed champagne over locker room visitors tip-toeing through an already soaked floor, Kelsey Plum happily took swigs of what she said was her first alcohol in six months and Chelsea Gray beamed with a trophy in hand.

It was the star-studded starters who led the Las Vegas Aces to their first championship in franchise history on Sunday night at Mohegan Sun Arena. But it was the play of the bench, often called out for its lack of production, that sealed the deal in a 78-71 victory.

The Sun were making a patented late push to force a Game 5 back in Las Vegas. Plum committed a flagrant 1 foul for a reckless closeout on DeWanna Bonner’s 3-point attempt with 3:46 on the clock and the Sun trailing by six. Plum, alcohol in hand and happily at the center of a media scrum, interrupted a question to call it “stupid, I know.”

Bonner hit all three free throws, Jonquel Jones added a jumper and Courtney Williams made one free throw and a pull-up from 18 feet following a shot-clock violation for the two-point lead. It was looking like the Sun’s Game 5 win against Chicago in the semifinals all over again.

Riquna Williams stepped in to end it. Plum hit her for a 3-pointer in the corner to get the lead back, 70-69, and again on an open look the following possession to make it 73-71. It was her 20-foot step-back jumper with 53.2 seconds left — again, assisted by Plum — that essentially called game. Plum added a bucket and Jackie Young hit a free throw for the final score.

That’s why Williams, a 10-year veteran who has spent the last two years in Las Vegas, is called the microwave.

“You just put her in and she heats up,” Plum said. “I knew it was only a matter of time because throughout the series, she got some really good looks and hasn’t hit ’em. So I knew it was coming. Especially, too, if they’re going to double the ball that is going to be there.”

To say the Aces relied heavily on their typical four All-Star starters, plus the snubbed Gray, is putting it lightly. They received 77.5 of their 90.4 points per game from them (85.7%) in the regular season. The bench’s 12.9 points per game ranked dead last in the league, and it dropped to 10.6 in the postseason

Bench play was a little skewed for the Aces this postseason because Dearica Hamby, an All-Star forward, came off the bench every game of the Finals after her return from a bone bruise in her knee. Williams was first off after her. She averaged 6.7 points a game in the regular season and 5.8 throughout the playoffs.

In Game 4, she scored 17 points on 6-of-11 shooting, 5-of-9 from 3-point range, with two steals and two rebounds. That trailed only Gray, who had 20 on 9-of-13 with five rebounds, six assists, one steal and one block. The now two-time champion was voted Finals MVP for her body of work.

Gray had been quieted in Game 3 when Sun head coach Curt Miller put the lengthy Bonner on her. The “point gawd” had been coy earlier in the series about giving up their secrets on what spacing they were seeing, but with the champagne sprayed, she gave it up.

“They were putting length on me for a long period of time, with either — if a guard was guarding me, their posts were extra extended. If DeWanna was on me, they were extra extended,” Gray said. “So our angles had to be different from the guards pulling up, so we can attack downhill. We wanted spacing and shooters on the floor. I knew we would go to our small lineup and space it even more and now your rotation is different, if you have Riquna Williams in the court versus somebody in the paint. So we were able to —”

(An inebriated Wilson, a character if there ever was one, interrupted to point out how fast Gray is talking. “But go ahead.”)

“Our spacing had to be different but I had to be aggressive on the ball first,” Gray said. “I was a little passive in Game 3 and scope it out, going into the pick-and-roll. So I knew I had to be aggressive.”

Head coach Becky Hammon and Gray adjusted, as did the rest of the team to eke out another Sun-style win. And when most needed, the bench showed it wasn’t here just for the vibes.

“We have competitors,” Plum said. “When we play white vs. black in practice, we go at each other. It was only a matter of time. Everyone’s number was going to be called in this series and her number was called and she responded.”