ATLANTA — Elena Delle Donne had just finished authoring another masterpiece Sunday afternoon when she leaned into the microphone to answer a question during the postgame news conference.

The All-Star forward’s fourth-quarter outburst, during which she scored or assisted on 13 of the Washington Mystics’ final 17 points, contributed significantly to an 87-84 win against the Atlanta Dream in Game 1 of the best-of-five WNBA semifinals, so teammate Natasha Cloud provided a simple explanation for the result before Delle Donne could get a word in.

“She’s the GOAT,” Cloud said of Delle Donne, using the acronym for greatest of all-time.

The dash of hyperbole notwithstanding, Delle Donne was virtually unguardable on the way to 32 points, matching a franchise playoff record, and 13 rebounds as third-seeded Washington wrested home-court advantage from the second-seeded Dream in front of an announced 5,086 at McCamish Pavilion.

“My teammates have trust in me in those situations to attack and try to make the right read,” Delle Donne said. “I was flowing today, so we kind of just ran the offense through me and I just kind of had to make reads and attack. If someone else is flowing, we run it through them, and that’s just kind of how our team is, super unselfish, and it’s why we’re successful.”

Game 2 is Tuesday night, but before then, Mystics coach Mike Thibault is certain to show his players video footage of a frenetic final few minutes in which guard Tiffany Hayes almost single-handedly willed the Dream to an improbable comeback.

The Mystics led by nine with less than two minutes remaining before Hayes scored six unanswered points in a span of 48 seconds. Hayes then had a layup come tantalizingly close to falling, but the ball fell off the rim with 33 seconds left.

Atlanta still trailed by three with 3.1 seconds left, when forward Jessica Breland’s 3-point attempt from the top of the arc rattled around the rim and out. The Dream had a final opportunity to force overtime off an inbounds play with less than a second left, but Mystics rookie Ariel Atkins swatted away a pass intended for Atlanta guard Alex Bentley (19 points), and the clock expired.

“That’s what Coach said, to guard the 3-point line,” Atkins said. “We knew that was the only way they could tie the game, or if we fouled them they could possibly win it, so we just were going to have to keep them off the 3-point line.”

Atkins chipped in on the other end of the court with 15 points, going 3-for-5 from beyond the arc, and was among four Mystics players to score in double figures. Washington is making its second straight appearance in the WNBA semifinals after being swept last season by the Minnesota Lynx.

This time, Delle Donne vowed after a 96-64 victory over the sixth-seeded Los Angeles Sparks in Thursday night’s single-elimination quarterfinals that the Mystics would be “ready and locked in.”

No player, it turns out, was more locked in Sunday than Delle Donne, whose scoring output included 10-for-10 from the foul line, marking the most made free throws in a postseason game for a Mystics player.

“You need to make Delle Donne shoot over the top of you and keep her off the glass because she shoots with a forward lean, which automatically kind of leads her right back to her missed shots,” Atlanta coach Nicki Collen said.

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