Leilani Mitchell didn’t really want to go to Bradenton, Fla., for two-plus months to live inside the WNBA’s bubble and play a pandemic-shortened season. It meant missing her son Kash’s second birthday and his first day of day care. And it meant leaving her partner back in Australia as a single parent.

More than that, this wasn’t exactly what the 35-year-old guard signed up for when she joined the Washington Mystics in February. At the time, she knew she was joining a stacked roster fresh off a WNBA title. Mitchell had been to the playoffs eight times, including runs to the Eastern and Western Conference finals. But she hadn’t played for a championship, and the opportunity to join such players as reigning MVP Elena Delle Donne, Natasha Cloud and LaToya Sanders was too good to pass up.

Now, here she was heading to Florida without many of the stars she expected to play with — Delle Donne, Cloud, Sanders and Tina Charles all opted out of the bubble, either for health reasons or to focus on social justice causes. Mitchell signed expecting to be a small piece of a title team. Instead, she has turned into a veteran leader of a team that secured the No. 8 playoff seed on the final day of the season and faces the No. 4 seed Phoenix Mercury on Tuesday in a single-elimination first-round game.

The Mystics (9-13) got off to a 3-0 start before losing 12 of 13 at one point, making their playoff hopes uncertain. On the home front, Kash didn’t fully understand why his mother was away for so long. He started boycotting video calls with Mitchell, which certainly didn’t help her mental health.

“I knew it was going to be hard,” Mitchell said. “I’d never been away for that long, especially because I was just home for the lockdown for two or three months and we really kind of got in a routine and I knew it was going to affect him. . . . It’s still a battle to get him on FaceTime. He wants to see me, but then at the same time it makes him upset and he runs away and says ‘No.’

“It is heartbreaking.”

By the middle of August, it might have been understandable if Mitchell harbored some doubt. But the Mystics finished the regular season on a 5-1 run, a stretch that Mitchell started with 20 points and 12 assists to spark a win over Chicago.

Mystics Coach and General Manager Mike Thibault had been telling Mitchell to shoot more, but the shots weren’t falling, which made her more hesitant. She made 6 of 10 shots from the field against Chicago, including 4 of 7 from beyond the arc, and the floodgates opened,

She averaged 11.3 points and eight assists over the final six games. She’s playing with more confidence, pushing the ball in transition and showing a knack for stepping up in key moments with baskets to kill opponents’ momentum. Mitchell is averaging 5.4 assists, which ranks fourth in the league.

“The long layoff in the offseason really hurt her,” Thibault said. “It probably disrupted her game some. She’s gotten in better shape as we’ve gone. She’s also gotten more aggressive as we’ve gone along. … On this team, we need her to be more aggressive offensively. We need her scoring.

“Just like she was saying to Emma [Meesseman], ‘We need you to shoot more.’ They’re saying it to her: ‘Lead us.’ ”

There was hope that the 12-year veteran would assume a leadership role on a team that became extremely young without Delle Donne, Charles, Cloud and Sanders. But Mitchell isn’t exactly the bossy type and her leadership role with the group actually grew away from the court.

A night spent on the couch in the villa of Myisha Hines-Allen, Meesseman and Ariel Atkins eventually resulted in her being named an honorary roommate. Team dinners began to take place when Mitchell started asking who was cooking what that night. Game nights became more frequent at Mitchell’s behest, a rotation of Spot It!, What Do You Meme?, Cribbage and Uno.

Hines-Allen said chemistry off the court led to success on it. The unassuming leader even sent a video to the team last week of new Duke coach Kara Lawson explaining the difference between working hard and being competitive as inspiration.

“She may look quiet, but she’s not quiet,” Atkins said. “She’s just calm. She has a very calm demeanor about her. I’m really glad she’s here, and I’m glad she decided to come. She’s been a big factor as somebody I can look to to ask those questions. Just try to calm us down.

“She’s smart. She’s kind of a brainiac even though she tries not to talk about it a lot. We ask her certain things about the game. It’s really fun to talk to her about basketball.”

Her knowledge of the Mercury could also be key for Tuesday’s matchup. Mitchell played the previous three seasons in Phoenix (13-9) and knows well how dangerous the Mercury backcourt of Diana Taurasi (18.7 points per game) and Skylar Diggins-Smith (17.7) can be. The pair are fifth and seventh in the league in scoring and rank Nos. 9 and 12 in assists. Those two plus defensive player of the year candidate Brianna Turner have found their groove since Brittney Griner left the bubble midseason for personal reasons.

Washington dropped both games to Phoenix during the regular season, which included a classic performance by Taurasi.

Mitchell and Kiara Leslie will draw the primary responsibilities of defending Taurasi and Diggins-Smith. Mitchell admitted playing her former team gives her a bit more juice entering the elimination game.

“One hundred percent, it feels good to knock out your old team,” Mitchell said. “I actually just had a little chat to [Taurasi] and Alanna [Smith] about an hour ago. … It should be fun. Obviously, it’s going to be competitive. It’s going to be intense. It’s going to be tough. It’s going to be a battle. We’re looking forward to it.

“At the end of the day, to knock them out would be a lot more sweet.”

Note: Hines-Allen, who averaged 24.3 points and 9.5 rebounds, was named Eastern Conference player of the week. It marked the second time this season the forward has won the honor.

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