She was provided with a personal trainer from age 7.

She was obsessed with being the best, always afraid someone was working harder than she was. Her skills seemed to be exceeded only by her maniacal work ethic.

Elena Delle Donne towered over the competition. The 6-foot-4 guard from Wilmington, Del., could handle the ball as easily as the expectations. She could shoot like Bird.

She was on the fast track to greatness until her heart began steering her in a different direction.

"About age 13, I thought, 'I don't know if I want to do this anymore,'" Delle Donne says. "'It's not fun.'"

But fun was never the objective. Delle Donne was the consensus 2008 Naismith National High School Basketball Player of the Year. She saw herself as the future of women's basketball. So did most everyone around her. She was supposed to follow her idol, Diana Taurasi, to Connecticut, win four national titles and become a superstar in the WNBA.

"I kinda was driving myself to be happy, and I was like, 'Well, you better like this!'" Delle Donne says. "'Because this is what it's gonna be.' And I was trying to force happiness upon myself, which I couldn't find in the sport."

Delle Donne was a Connecticut Husky for all of 48 hours. She says it took her only that long to realize she lacked the passion to play the sport at the highest level. She says she could no longer pretend.

Connecticut coach Geno Auriemma doesn't pretend to understand why the top recruit in America left his school in the middle of the night in June.

"I don't know how you can play that much basketball and be that good at it and say, 'I hate it since the time I was 13.' To me, those two things don't go together that you would be that good at something and not enjoy any of it. It's hard for me to come to grips with," Auriemma says.

Elena Delle Donne, a McDonald's All-American, walked away from basketball and decided instead to play volleyball at Delaware. Joe Murphy/NBAE/Getty Images

"I'm still not able to see how that makes any sense. I didn't understand it and haven't understood it right from the beginning."

Auriemma is not pining for Delle Donne. His No. 1-ranked Huskies are unbeaten and virtually unchallenged, winning their games by an average of nearly 40 points. But he says he has never coached a player who left his program because she lost her passion for the game.

"Nope," Auriemma says. "Not anybody that was any good -- let's put it that way. Never experienced anything like that from somebody who is really talented and successful.

"How could [you] get to be the best if you don't have some passion for it?" he asks. "It would've come out a long time before. A lot of kids probably don't like playing piano, but I don't know that you become the best if you don't like it at all. At some point, you would screw it up on purpose, wouldn't you?"

Delle Donne does not expect Auriemma to understand. She wasn't sure anyone would. Perhaps that's why it took her so long, about five years, to come clean.

Connecticut coach Geno Auriemma says fans might never know why Delle Donne quit basketball. Ned Dishman/Getty Images

"You can't understand it unless you're in my shoes," Delle Donne says. "And that's the thing: You don't understand burnout unless you've been burned out. And it's something you can't even explain. It's just doing something you have absolutely no passion for."

When coaches would ask the teenage Delle Donne whether she was feeling drained by a sport she played 12 months of the year, she would tell them burnout was not in her vocabulary.

"It's hard to explain, and people are like, 'How are you doing this?' Like, 'Look at your future, do you not see it?'" she says. "And I'm like, 'I do see what I could have been.' And it's harder for me than it is for anyone else because I see these God-given abilities that I've been blessed with and I can't go forth with them."

When Auriemma released Delle Donne from her scholarship, she transferred to the University of Delaware, 20 minutes from her home. She plays volleyball in front of crowds of fewer than 500 fans instead of the 10,000 raucous rooters who fill the Huskies' Gampel Pavilion for women's hoops games.

She no longer plays basketball. She recently was named to the Colonial Athletic Association All-Rookie Team for her new sport.

"Now that I play volleyball, I know how it feels to have a passion for your sport," she says. "Before, I just thought, 'Maybe everyone's faking it because this is horrible.'"

Delle Donne says she was burned out on basketball years ago. She feels passion for volleyball now. Jonathan Daniel/Getty Images

Delle Donne, who turned 19 on Sept. 5, says she's too young to rule out a return to basketball. Yet she says she has not picked up a ball in months and has no interest in watching the game on television unless her friends are playing.

"I'd rather be a face for happiness and doing things that you have a passion for, rather than faking it and pretending like I'm this face of women's basketball when I can't stand the sport at all," she says.

Auriemma says we might never know why Delle Donne pushed basketball aside. Or why she chose to leave the stage at the moment an entire nation finally would get to see her shine.

"I can't imagine Elena Delle Donne didn't love playing basketball," he says. "I can imagine she may not have loved the stuff that came along with it. That, 'I got to be Elena Delle Donne,' or, 'I've got to play at a certain level.' Maybe that makes more sense than, 'I hated the game since I was 13.'

There's something missing, he says like a detective still searching for leads.

"There's something not quite out there yet," he says. "There's a lot of things that don't fit together."

Mark Schwarz is a reporter in ESPN's Enterprise Unit. His work appears on "Outside the Lines."