Guard Ivory Latta, shown earlier this week, and the Washington Mystics will open the WNBA playoffs in Atlanta on Thursday night. (Toni L. Sandys/The Washington Post)

About an hour before tipoff Sunday afternoon, Washington Mystics Coach Mike Thibault sat in his familiar courtside folding chair trying to figure out whether his former team would do his new one a favor from more than 350 miles away.

A gaggle of team employees stood behind him, huddled over a cellphone to watch the final moments of the Connecticut Sun’s overtime victory against the Indiana Fever, a result that opened the door for Washington to jump the Fever in the WNBA standings.

Combined with the chance to finish with a .500 record or better for just the fifth time in franchise history, it would be all the motivation the Mystics needed in their regular season finale. Washington overcame a sluggish start to beat the New York Liberty, 70-52, at Verizon Center and secure the Eastern Conference’s No. 3 seed when the WNBA playoffs begin this week.

The Mystics (17-17), who won just 11 games combined the past two seasons, will face the Atlanta Dream (17-17) in a best-of-three Eastern Conference semifinal series starting Thursday in Atlanta. Game 2 is scheduled for Saturday night at Verizon Center.

“Considering where we were at the start and where we were a month ago, being back to .500 and being in this position feels good,” said Thibault, who qualified for the playoffs during eight of his 10 years with Connecticut. “Now we have a new season to start.”

Thibault hoped to avoid facing top-seeded Chicago in the opening round of the playoffs because of an imposing front court that gave the Mystics fits all year, and New York proved his point by grabbing nine offensive rebounds in the first half Sunday against the Mystics.

But Washington didn’t allow a second-chance point after halftime, never trailed after the first quarter — when it started the game shooting just 4 for 17 from the field — and committed a season-low eight turnovers.

Forward Kia Vaughn finished with 10 points and 12 rebounds on an afternoon when second-leading scorer Crystal Langhorne was limited to three points on 1-for-9 shooting.

Rookie Tayler Hill was the star of the second half, nailing three three-pointers as the Mystics pulled away from the Liberty (11-23). The Ohio State product tied her career high with 16 points.

After hitting multiple three-pointers just three times in her first 29 professional games this year, Hill has done it four times in the past five games. She said “the game has slowed down for me, and I’m more comfortable,” but Thibault believes there’s more to it than that.

“She stopped putting as much pressure on herself as she did at the start of the year,” he said. “Being one of the top rookies, I think she felt she needed to live up to being the fourth pick, and we kept telling her, ‘You just have to fit in.’ ”

On the other end of the spectrum was Liberty guard Katie Smith, who scored seven points in the final game of her professional career Sunday. The 15-year veteran will retire as the second-leading scorer in WNBA history. She played for the Mystics in 2010, the last time Washington qualified for the postseason.

“It’s very meaningful. You can sense it,” point guard Ivory Latta (12 points) said. “Everyone’s excited. Going from last to now being the third seed, that’s a big jump.”

SUN 82, FEVER 80: Izzy Castro Marques made two free throws with 1.9 seconds left and finished with 19 points to lead Connecticut in Uncasville, Conn.

Karima Christmas scored a game-high 21 points to lead Indiana, which dropped to the No. 4 seed in the Eastern Conference.

SILVER STARS 97, DREAM 68: Danielle Adams scored a franchise-record 39 points as host San Antonio closed a disappointing season with a rout of playoff-bound Atlanta.

SPARKS 89, MERCURY 55: Candace Parker and Jantel Lavender each scored 16 points to lead host Los Angeles past Phoenix in a preview of an upcoming playoff series.