Nineteen years ago, a sixth-grader gave the WNBA one of the most influential figures of its now 25 years of existence. Well, she and George Karl did.

Carly Thibault-DuDonis was early in her budding basketball career when she made an astute observation to her dad: She noticed the girls who played ball weren’t receiving the same instruction as the boys.

“ ‘Women’s basketball — not even the W — women’s basketball needs more good coaches,’ ” Mike Thibault recalled his daughter saying, referencing the WNBA. “ ‘And this is what I need, what my friends need, what the game needs.’ It was pretty interesting for a young person to say that.”

The thought came at a time of transition for the Washington Mystics’ coach. He was on his way off the Milwaukee Bucks’ staff in 2002 after a falling-out with Karl, then the Bucks’ coach — a rift that, Thibault said, he was unaware of. He wanted to be a head coach again after serving as an NBA assistant for 10 years with the Los Angeles Lakers, Chicago Bulls and Bucks. Friends spoke highly of the WNBA and suggested he consider the still-young league.

The rest is history: Thibault landed with the Connecticut Sun in 2003, has been named WNBA coach of the year three times, became the winningest coach in league history, won the 2019 championship with the Mystics and reached 350 WNBA wins last week. No other coach has 300.

The Mystics won 11 of 68 games during the two seasons before Thibault, who is also the club’s general manager, joined the franchise ahead of the 2013 season.

“Mike Thibault is the winningest coach in the WNBA for a reason — he can see the game, player skills, team chemistry and how to expose opponents’ weaknesses like no other,” Mystics majority owner Ted Leonsis wrote in an email. “We were looking for a visionary leader to deliver. That’s what Mike has done.”

Basketball has always been a family affair for the Thibaults. That love for the game transcended gender 20 years ago and continues to do so today. Thibault-DuDonis remembers the early days in Connecticut, heading to the team facility with her dad after picking up breakfast from McDonald’s to devour as Thibault handled office work before heading to the court. After that, it was four to five hours in the gym with the team every day, shooting and rebounding for players such as Lindsay Whalen and Nykesha Sales. Her brother, Eric, now associate head coach for the Mystics, also was around; he worked with the Sun while still in college.

Connecticut drafted Whalen, who went on to win four WNBA championships with the Minnesota Lynx and two Olympic gold medals, in 2004, and she became an older sister of sorts for Carly. Seventeen years later, Whalen is the coach at the University of Minnesota and Thibault-DuDonis is on her staff. At the same time, Thibault, now 70, continues down the path that his daughter set him on, with no end in sight.

“We always used to joke that he would coach until he died,” Thibault-DuDonis said with a laugh. “I think he’s probably made this comment that he’s going to be yelling at a ref and that’s how he’d go. Once I kind of started to really love basketball, he realized that the women’s game does have a ways to go. … He always just treated it like it was no different than the NBA, as it should be.”

Dan Hughes will never forget beating the Mystics for the 2018 WNBA championship with the Seattle Storm. The two-time coach of the year retired this season, but he vividly remembers Thibault coming into the Storm’s locker room to chat despite the Mystics’ loss. The two are longtime friends, and Thibault was genuinely happy for Hughes despite losing the opportunity for his own first title. Hughes called it “class beyond class.” When Thibault reached 300 wins, Hughes sent him a bottle of wine from San Antonio Spurs Coach Gregg Popovich’s vineyard.

If you ask Hughes, the list of what makes Thibault unique is lengthy. He pointed to longevity, coaching ability and player evaluation. Even more important, Hughes noted, has been the way he gives back to the game, empowers players to be themselves and backs their social justice interests with action, not just words.

“I will forever, forever be shaped by the presence he had in that moment,” Hughes said of the 2018 championship. “Every time I’ve been around Mike Thibault, it made me better as a person and it made me better as a basketball coach. Both of us want to empower women and want to empower the WNBA. … The thing that Mike has done, and I’d like to think that I join him in that, is that we see the WNBA as an elite basketball league, and we want to do everything we can to empower the audience of America and the world to see it that way. And I think his coaching has done that.”

Hughes said Thibault knows he is in the right spot and doing the right things, and his longevity is proof. And Thibault noted that, regardless of profession, people need to understand their personality and find what fits. Thibault has been able to have an impact on the growth of the league while allowing women to be themselves, market themselves and vocalize what’s important to them.

Overlooked players such as Ariel Atkins, Natasha Cloud, Emma Meesseman and Myisha Hines-Allen have blossomed on his watch. So have those who had garnered more recognition before coming into the league; Tina Charles and Elena Delle Donne were named WNBA MVP while playing for Thibault. And now both of his children are coaches, with Eric in line to be a lead candidate for the Mystics’ job whenever Mike steps away.

“I’ve never talked to a player who didn’t enjoy playing for him,” said Hall of Famer Rebecca Lobo, who played for Thibault with the Sun. “One of the big things when you’re a player is you want to feel like your coach is in your corner, that your coach wants you to succeed as much as he wants the team and himself to succeed or the team and herself to succeed. And I think his players feel that. I certainly felt that. I felt like his decisions were based on, ‘All right, what’s best for the team and what’s best for these women?’ ”

That sense of purpose leads to perspective — or perhaps vice versa.

Either way, Thibault is adamant about his players and those around him having something more than basketball in their lives. That’s why he didn’t hesitate to let Charles miss a game last week to attend the Tribeca Film Festival premiere of “Game Changer,” which she directed and produced. That’s why he continually pushes the team to be active in social justice causes.

He is a product of the 1960s and 1970s who lived through the Vietnam War. He started college as a music major who played drums, trombone and piano. He appreciates that the atmosphere of the WNBA allowed him to be around to see his kids grow up. Being the oldest of nine siblings developed empathy for all of the other things people deal with beyond the narrow focus of pro sports.

“Life’s too short to just have your whole life be about basketball,” Thibault said. “A lot of people know me only as a basketball coach. I don’t resent that, but I also know that I can’t let basketball be my identity.I’ve always known for players, anyway, that this stuff ends whether it’s four years into it, 10 years. You’ve got to have something else you’re passionate about besides playing. So those things always take precedence in life.

“Because we have our score in the paper every day and because we all talk to the media every day, it’s a big deal. But basketball is not life.”

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