Contrary to popular belief, Serena Williams wasn't born with her powerful, game-changing forehand. The iconic stroke was honed over the year thanks to thousands of hours spent on the public courts with her mother, Oracene, her father, Richard and big her sister, Venus. 

But if it wasn't for Serena's punk-rock tendencies, that forehand may never have been what it became. 

In Williams' new eight-part documentary series on ESPN, "In the Arena: Serena Williams," the 23-time major champion revealed a skateboarding accident seemed to turn her forehand from a liability to a weapon seemingly overnight.

"In the Arena" streams every Tuesday on ESPN+.

"All my dreams weren't on the tennis court," Williams said in Episode 1. "I learned guitar and started listening to Green Day. I became a low-key punk rocker because I loved Bad Religion and Rancid. Back then I loved to skateboard. That's how I got a good forehand. 

"One day I was at school and I didn't want to be there so I just took my skateboard out and I went skateboarding in the neighborhood and fell and hurt my wrist really bad. I never told my dad. 

"I couldn't really hit backhands, so I was like I want to work on my forehand today, I want my forehand to get better."

Williams, who described herself as undersized and underpowered, suddenly started to rip the ball.

"We remember her forehand getting much bigger after that," Venus said, laughing. "I thought maybe I should have fallen." 

It was a pivotal moment for Serena, who described herself as the antithesis of her big sister at the time. 

"For me it was always about Venus and Serena," Serena said. "She was the phenom. My whole game was hitting lobs and drop shots. It's nothing like my game today. I just wasn't strong enough. So I would hit lobs and then I'd wait and I'd move my feet really good and  I would hit drop shots. My matches would be, like, two hours.

"I was that kind of player that you hated playing in juniors." 

In "In the Arena," Williams takes fans inside her career, from its inception on the public courts of Compton, California, all the way through her illustrious professional career. Williams takes viewers inside some of the biggest matches of her career, with honest insight into the wins and losses that defined her career. 

In Episode 1, Williams recalls bouncing back from her dispiriting professional debut, a 6-1, 6-1 loss to Anne Miller in the first round of qualifying at Quebec City in 1995 to winning her first Hologic WTA Tour tournament four years later at the 1999 Paris Indoors, where she overcame the partisan crowd to beat Amelie Mauresmo in the final. 

20 years after her first Grand Slam title, we look back at Serena Williams' 1999 US Open run. Footage courtesy of the USTA.

That title sparked her memorable 1999 season, which culminated in her first Grand Slam title at the US Open. There, she primed herself to face No.1 Martina Hingis, who defeated Venus one round earlier in the semifinals. 

Watching Venus lose, Serena's competitive intensity ramped up from there. 

"We were doing the coin toss -- and I never talked about this -- but I lose the coin toss," Serena said. "I lose the coin toss and the referree and the referee says to Martina, serve or receive."

Hingis chose to serve.

"I looked at her and I said 'Are you sure about that?' and she was, like, startled," Serena said.

She would win in straight sets. 

"Years later, I remember thinking I can't believe I said that," Williams said.