UNCASVILLE, Conn. — Elena Delle Donne isn’t getting much sleep these days, and the reason has nothing to do with frayed nerves, with her Washington Mystics needing one victory for the first WNBA championship in franchise history.

The league MVP instead lies awake, occasionally in excruciating pain, because of a herniated disk that has plagued her since leaving Game 2 last Tuesday night in the opening minutes when she felt a pinch in her back reaching for a rebound.

Part of the process that got her ready to play in Sunday’s 94-81 win against the Connecticut Sun in Game 3 included having her wife, Amanda Clifton, adjust pillows under her back multiple times each night to find the most comfortable angles to allow for even a modest amount of rest.

“It’s like a whole thing,” said Delle Donne, discussing her treatment routine in detail for the first time Monday afternoon. “There’s only two positions I can lay in where I’m not in pain. It’s just a lot of moving around through the night and just trying to find a little bit of sleep when I can.”

Delle Donne still managed 13 points and six rebounds in 26 minutes despite getting bumped and jostled repeatedly as Sun players attempted to throw her off her game.

The pain, Delle Donne revealed, has been so acute — it’s on her mind every second she’s on the court, she said — that she turns to meditation to block out the discomfort and persevere.

“This series deserves her to be in it,” Sun Coach Curt Miller said. “I’m excited, frankly, that she’s in it. It doesn’t make it easy to guard, doesn’t make it any easier, but this league, this series deserves the best players on the floor, so I give her credit for giving what she’s got, but that’s what this league is about.”

During Game 3, Delle Donne played in relatively short intervals, coming out either to rest while standing behind the bench or keeping her back loose pedaling on a nearby stationary bicycle.

With rest being a priority not just for Delle Donne but other players nursing ailments, including Ariel Atkins’s back spasms, the Mystics eschewed a full practice Monday, with Coach-General Manager Mike Thibault presiding over a light shooting session at Mohegan Sun Arena.

The streamlined workload has served Delle Donne well, especially down the stretch Sunday, when she drove to the basket and banked in a shot that blunted a Sun rally, effectively allowing the Mystics enough breathing room to run the clock and shoot free throws with Connecticut forced to foul.

“That was the one where I was like, ‘I might be done after this,’” Delle Donne said. “But if we can score here, it’s a big enough moment to end the game. It feels like I have a pole up my back. Just very straight up and can’t move.

“I guess I have experience playing injured in these freakin’ Finals.”

Delle Donne was referring in part to last season, when she suffered a bone bruise in her left knee during Game 2 of the WNBA semifinals on the road against the Atlanta Dream.

She played with the discomfort in the Finals, in which the Seattle Storm swept Washington.

Delle Donne also battled back pain in the 2014 WNBA Finals, when she was with the Chicago Sky. She had played in just 16 regular season games that year but was on the court for all nine of the Sky’s playoff games, including a three-game sweep at the hands of the Phoenix Mercury.

The pain of a herniated disk, Delle Donne said, is far worse than any she has endured in her career, yet the allure of winning a championship compels her to do whatever possible to contribute, even if it means acting as decoy and allowing teammates to get open looks.

She’s also limited defensively, although at 6 feet 5, she remains disruptive at times when guarding Sun all-star Alyssa Thomas. Thibault switched Delle Donne onto Thomas, a 6-2 forward, after she had guarded 6-6 center Jonquel Jones in Game 1.

In Game 3, Thomas scored 13 points, her fewest of these Finals, but added nine assists and eight rebounds while playing with a torn labrum in each shoulder that she has been dealing with for months.

“I mean, it’s the Finals. I wouldn’t expect anything less,” Thomas said of Delle Donne. “There’s not much basketball left to be played, and she’s a huge part of her team, so I expected her to be out there.

“It’s not easy playing through injury, but she’s a competitor, and yeah, it’s just what you do for your team.”

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