LAS VEGAS — The raucous crowd at Mandalay Bay Events Center was treated to one of sports’ true joys Tuesday night: an old-fashioned duel between perhaps the WNBA’s most expressive and least expressive superstars.

In one corner, Liz Cambage. The Las Vegas Aces’ 6-foot-8 center towers over, and bulldozes through, her opponents. She commands defensive attention, and the viewer’s attention, like a magnet. Cambage recently posed nude for ESPN the Magazine, then arrived to Game 4 of the WNBA semifinals Tuesday wearing a T-shirt bearing one of the images from the photo shoot.

In the other, Elena Delle Donne. The Washington Mystics’ MVP forward glides across the court with economical motions, turning time and again to well-honed moves that allow her to create openings that often seem to measure a fraction of an inch. She has seemed to wear two masks: a clear Velcro model to protect her broken nose, and a blank visage that keeps observers from reading her inner monologue.

One approach is not necessarily superior to the other, but the quiet way prevailed Tuesday.

The Mystics defeated the Aces, 94-90, to advance to the WNBA Finals for the second straight season. Delle Donne and Cambage each scored 25 points to lead their teams as the all-stars went back and forth in front of Los Angeles Lakers stars LeBron James and Anthony Davis, who took in the tense contest from courtside seats.

Sin City knows a thing or two about hyping heavyweight fights, and this series’ headliners played their roles, perhaps unintentionally, at Monday’s practice.

Here was Cambage, relaxing in a chair at practice, explaining why her physical style and demonstrative personality have made her a lightning rod for opponents. “I’m a cheeky little s---,” she joked with a mischievous smile and her Australian accent.

There was Delle Donne, her face set in a tense stare, refusing to bite on questions about Cambage’s Game 3 trash talk. Cambage had suggested that the Mystics’ frontcourt players might need to hit the weight room if they wanted to guard her, but Delle Donne couldn’t have cared less about the sentiment or the social media fallout. She gritted her teeth through the group interview with the practiced boredom of a traveler in a TSA line at the airport.

For most of Game 4, they stuck to their differing scripts.

As Cambage racked up 25 points and 12 rebounds, the Aces’ fans pleaded for Coach Bill Laimbeer to continue “feeding the beast.” The Mystics’ undersized center, LaToya Sanders, battled hard, but she eventually fouled out in 25 minutes part because of the physical mismatch.

The high stakes and high-intensity environment brought the best out of Cambage. She cupped her hand to her ear to encourage the crowd to yell at the refs. She screamed loudly and fist-pumped like Tiger Woods after a second-half basket. She chest-bumped one of her teammates after a late blocked shot. She played with such ferocity that she crashed to the court time and again, as if gravity was a new concept and she was a designated product tester.

Delle Donne wore her trademark fixed gaze, preferring polite claps of encouragement and silent nods as the pressure mounted. Las Vegas’s bids for momentum never shook her. When the crowd neared its peak levels with the Aces leading by one to close the third quarter, Delle Donne opened the fourth with total poise.

The 6-5 forward hit a tough up-and-under to quiet the crowd, grabbed a big offensive rebound to set up Emma Meesseman’s three-pointer on a broken play, and then she drained a three-pointer from the top. Later, she stretched to get a hand on a pass and twisted to finish a tough off-balance shot in traffic, then drained a picture-perfect turnaround jumper to give the Mystics a three-point lead with less than three minutes to play.

But Delle Donne did it all exactly as she had promised: within the team concept.

“Our offense is so fluid that I don’t try to force it,” she had explained on Monday, when asked whether she ever feels tempted to assert herself when a game is slipping away. “That’s not the way we play. When we play one-on-one, it’s not good basketball and it doesn’t work for us.”

Delle Donne’s trust was rewarded.

After an ugly showing in Game 3, Washington’s offense responded by shooting 43 percent on three-pointers and four Mystics players finished in double figures. And it was Meesseman, who was held in check for Game 3, who hit a clutch midrange jumper with 29 seconds left that extended Washington’s lead back to three and forced Las Vegas to call timeout.

Finally, sensing the weight of the shot, the reserved MVP couldn’t contain herself any longer. As Washington returned to the bench, Delle Donne sought out Meesseman for congratulations and yelped what sounded an awful lot like an unprintable curse word.

Moments later, the Mystics were on the court celebrating their victory, which sets up a championship series against the Connecticut Sun. Delle Donne again ran after Meesseman to deliver forceful, grateful high fives.

“I swear I was about to kiss her,” a giddy Delle Donne joked later, knowing her first WNBA championship is now just three wins away.