The No. 1 Washington Mystics survived an offensive showcase in game 1 of the WNBA semifinals on Tuesday night, taking a 97-95 win over the No. 4 Las Vegas Aces.

The Aces, who advanced via a jaw-dropping shot by Dearica Hamby, had a chance at tying the game but Kelsey Plum didn’t get the foul call at the final buzzer.

The No. 2 Connecticut Sun protected their home court as they’ve done all season long with a 84-75 victory over the No. 3 Los Angeles Sparks in the early game.

The best-of-fives semifinal series continue Thursday on ESPN2. The Sun and Sparks begin at 6:30 p.m ET with the Mystics and Aces to follow.

Mystics escape with victory over Aces

Aces coach Bill Laimbeer was furious no foul was called as the Mystics celebrated a game 1 victory after a nine-day break. Plum took a shot as time expired to tie the game and the Mystics’ Elena Delle Donne ran into her from behind.

But there was no call and the most efficient offense in history escaped with a key win.

Delle Donne’s 11-foot jump shot with 30 seconds left gave Washington enough of a cushion. The team led by 13 points in the fourth following a back-and-forth third quarter, but watched it evaporate to two with 1:33 to play.

Delle Donne scored 24 points with six rebounds, six assists, one steal and one block. In the third she made her 41st consecutive playoff free-throw, a WNBA record.

As the Aces keyed in on defending the leading MVP candidate, Emma Meesseman made them pay with a season-high 27 points. She had 10 rebounds and three assists.

Kristi Toliver, played for the first time in more than a month due to a knee injury, scored five of her eight points in the fourth quarter to stake the win. Her step-back 3-pointer to close the third — her first points since Aug. 5 — broke yet another tie and gave the Mystics the 76-73 advantage. It was the first time since 2014 she came off the bench.

The three Aces All-Stars paced the squad. Liz Cambage had a double-double off 19 points and 12 rebounds, though she was kept largely quiet in the second half. A’ja Wilson scored a team-high 23 points with seven rebounds and three blocks. Kayla McBride had 19 points.

A fired-up Plum added 16 points off the bench, shooting 6 of 10 overall (including going 4-for-4 in the first) and hitting two of three 3-point attempts. Her bucket with 28 seconds left gave the Aces a final shot once Cambage secured a defensive rebound.

As she did against the Sky, Plum drilled a buzzer-beating 3-pointer at the half that gave the Aces a 57-50 lead.

It was a sharp-shooting beginning for the Aces. Las Vegas hit 61.8 percent of its shots (21-of-34) and hit four of five 3-point attempts along with all 11 free-throw tries as a team. They finished at 50 percent overall and 53.8 percent from 3-point range. The Aces also out-rebounded the Mystics, 42-30, but had 13 turnovers to the Mystics’ six.

Washington shot 42 percent (21-of-50) and only 26.3 percent from behind the arc, a notable stat since the Mystics attempted 19 (and made five). By the end they’d improved to 44.7 percent and 39.3 percent, respectively.

Sun pull away from Sparks with even attack

It was Alyssa Thomas’ night to shine for the Sun, who went 15-2 at Mohegan Sun Arena in the regular season. It was the Sun’s first postseason victory since 2012.

She had a double-double with 22 points, including the team’s first 11, and 10 rebounds along with five assists and four blocks.

Thomas is playing through torn labrums in each shoulder. She was in for all 40 minutes of the victory.

“She doesn’t really take many possessions off,” Sparks coach Derek Fisher said postgame, complimenting her play on both ends of the court.

The Sun broke out of a tight game in the fourth quarter, outscoring the Sparks, 25-17.

Jasmine Thomas scored 19 points, including three 3-pointers, with eight assists.

After a bucket by Jonquel Jones more than four minutes into the game broke Alyssa Thomas’ scoring streak, Jasmine Thomas hit back-to-back 3-pointers, including one at the buzzer, to give the Sun a 21-14 lead. They held it until nearly halftime.

Connecticut had four players in double-digit scoring. Jones had 16 and Courtney Williams added 15. The Sun’s starting five of Shekinna Stricklen, Alyssa Thomas, Jasmine Thomas, Jones and Williams took the tip together for their 35th game this season after doing so for all 34 during the regular season.

Candace Parker scored a game-high 24 points for the Sparks, who eliminated the reigning champion Seattle Storm on Sunday, with six blocks and 10 rebounds. Nneke Ogwumike joined her with a double-double of 20 points and 10 rebounds. Each had three assists. No other Sparks player scored more than eight points or had more than four rebounds.

“We for sure need some support in the back court,” Fisher said. “In terms of our shooting in the back court, it wasn’t there much for us tonight.”

The Sparks shot better from the floor and the free-throw line, but had 19 total turnovers to the Sun’s 10. Their largest lead was four points.

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