WASHINGTON (AP) — The Washington Mystics were thrilled to pull out a close win in the playoffs.

Elena Delle Donne scored 24 points and hit a crucial turnaround jumper late, Emma Meesseman added a career postseason high 27 points and 10 rebounds, and the Mystics held on for a 97-95 victory over the Las Vegas Aces in Game 1 of their WNBA semifinal series.

It was Washington's first win all year by a single possession, one in which the Aces missed a game-tying runner at the buzzer.

"It was stressful," admitted Delle Donne, helped the Mystics to a 26-8 regular season record and the top playoff seed. "We haven't had many of those moments. And to get one of those in the semifinals is big. To be able to gut it out is huge for us."

Meesseman also bested her regular-season high of 25 for the Mystics, who were playing their first postseason game since being swept by the Seattle Storm in last year's WNBA Finals. Meesseman wasn't a part of that team, after taking a leave of absence following the 2017 season.

"She's been preached at all year by her teammates and coaches that she's the missing piece from a year ago," Mystics coach Mike Thibault said.

In her first game in more than a month, Kristi Toliver added eight points, including a falling away, contested 3-pointer that stretched Washington's lead to 13 in the fourth quarter, an advantage that just barely held.

"Kristi had some Kristi moments," Delle Donne said. "Thank God."

A'ja Wilson scored 23 points for Las Vegas, which twice got the deficit as close as two points in the final moments. Liz Cambage had 19 points and 12 rebounds, while Kayla McBride added 19 points.

Kelsey Plum had 16 points and nine assists, and missed a runner to force overtime two days after Dearica Hamby's 35-foot runner decided the Aces' 93-92, second-round win over Chicago.

After Toliver's 3 made it 92-79, the Aces scored nine straight points to close the deficit to four, while twice forcing the Mystics into a shot-clock violation with the ball in Delle Donne's hands.

Wilson's drive and layup closed it to 95-93 with 1:33 left, convincing Mystics coach Mike Thibault to call timeout. Following missesd on each end, Delle Donne's turnaround stretched the lead to four with 32 seconds to play.

"They made some big shots tonight, I give them a lot of credit for that," Aces coach Bill Laimbeer said. "They made some shots down the stretch. The lulls that we had hurt us. And hopefully that was a learning experience."

Plum answered with a layup. Then Delle Donne missed a jumper with the shot clock expiring as the Aces opted not to foul.

Plum received an outlet pass and raced inside the arc, but her 20-footer wouldn't fall.

TIP-INS

Aces: Shot 73.3 % (11 of 15) during the opening quarter but still trailed at the end, 30-27. ... The series opener marked the Aces' first game in a WNBA semifinal series since making a run to the 2008 finals, when the team was located in San Antonio.

Mystics: Did not commit a turnover in the first quarter and committed only two by halftime ... Toliver entered with 4:17 left in the first quarter to a standing ovation. It was her first action since Aug. 8 (knee bruise).

CAN YOU HEAR ME?

Laimbeer could not tell whether Plum was fouled on her final shotcont, but he was frustrated he wasn't granted a timeout to set up a play for a better look.

"I was standing next to the referee by design," Laimbeer said. "As soon as they missed the shot, I would be yelling 'Timeout! Timeout! Timeout!' ... I yelled it five times. And she even looked at me as I was yelling and made a conscious decision not to call timeout. I do not understand why. I think the league should make a little bit of an investigation."

REST OR RUST?

With their playoff double-bye, the Mystics were playing their first game in nine days. They were just 1-2 on five or more days' rest in the regular season. The fourth-seeded Aces also had a week to wait before their win Sunday.

UP NEXT

Game 2 of the best-of-five series is Thursday in Washington.

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