The youngest of five sisters, Serena, now 27, learned tennis from her dad, Richard, on the public courts in the blighted Los Angeles suburb of Compton.

Best anyone can recall, I was three years old. My parents took us to the public courts in Lynwood, Calif. The courts were in sorry shape. There was broken glass. Weeds. We could hear gunshots from drive-by shootings. My older sisters had been playing, while I had been trudging along, but one day my dad announced I was ready to take my swings, too. He put a racquet in my hand. Then he started soft-tossing. "Just look at the ball," he kept saying in that patient Louisiana drawl I'd come to hear in my dreams. "Just swing."

Daddy believed tennis was our ticket out of Compton. What people don't realize is my mom was with him every step. I actually spent more time hitting with my mom than with my dad.

Away from tennis, we were a regular family. We sisters all fit into particular roles. Tunde was the forgiver; she had a heart of gold. Isha was the caretaker; Lyn was our play pal, always up for a new adventure. Venus [15 months older than me] was my protector. And I was the princess, everyone's pet. Looking back, I think I was more like a pest! All five girls shared a bedroom, with four beds. Do the math: it meant one of us was odd girl out—me. Every night, I'd have to bunk with a different sister. That might have messed with my sense of belonging, but instead of feeling like I didn't quite belong anywhere, I felt like I belonged everywhere.

I got away with a lot. My goodness, I had a rotten streak. I was horrible—a real witch! Of course, it's significant to note that I never thought of myself as cute. When I look back at pictures, I'm put in mind of how awkward and ugly I used to feel. [Not] all the time. My sisters were always dressing me up, fussing with my hair, basically putting me to work like a model to try out different looks they were considering for themselves. I loved the attention.

When we were kids I wanted to do everything just like Venus. She was taller, prettier, quicker, more athletic. And certainly nicer. There was no living up to her. I tried. Whenever we went to a restaurant, my mom would make me order first, because if I didn't I'd just order whatever Venus ordered. Venus never held it over me, that her tennis game was bigger and better. "Your time will come," she used to say.

When she was 8, Serena squared off for the first time against her sister.

It was a 10-and-under tournament and I was the youngest girl in the field. Still, I won all my matches. But that put me in the finals against Venus. Sure enough, she beat me easily. I should have been happy for V. But I was disappointed—and I couldn't let on! They gave me a nice silver trophy, but I just kept looking at Venus's gold trophy. Venus could see I was upset. She came up to me after and said, "I've always liked silver better than gold. Want to trade?" To this day that's the most meaningful trophy I've ever received.

In September 2003 Serena's 31-year-old sister Tunde, a beauty salon owner who was like a second mother to Serena, was killed after she was struck in the back of the head by a stray bullet as she sat in an SUV driven by her boyfriend.

I was in Toronto, shooting a television show. Lyn was along for the ride. When the phone rang at about four in the morning, it was like a bad dream. It was my mom. Her voice was calm but confused. She said, "Have you heard from Tunde? I can't reach her. I think maybe something's happened. Maybe she's been involved in a car accident, or a shooting." The call didn't make a lot of sense. It wasn't that late in California. Maybe she'd gone out to a late dinner. I said, "Mom, I've got a shoot tomorrow. I'm sure Tunde's fine."

Still, I called Tunde's house. One of my cousins answered. That's when I heard. That she'd been in an accident. That she'd been shot. Everything sort of half-registered, but then the whole dark truth took shape. "She's gone, Serena," [my cousin said]. "I'm so sorry."

Gone? Tunde? I'd just spoken to her earlier in the day. She was so excited about this show I was working on, how well Venus had played that summer. I know it's a cliché but she really did have her whole life ahead of her. Gone? Her children needed her. Her parents needed her. Her baby baby baby baby sister needed her. I pushed the thought out of my head. I said, "What do you mean, gone? Is she out?" "No, Serena," my cousin said. "There's been a terrible accident. I'm afraid she's passed." I was screaming and crying. I dropped the phone. I couldn't think what to do with my hands.

What happened was Tunde drove over to Compton, our old neighborhood, with this guy she'd just started seeing. Some kind of argument took place. I can't imagine Tunde arguing over anything, so I'm guessing the guy she was with was doing the talking. Anyway, somebody pulled out a gun, and shots were fired into the SUV Tunde was riding in. Just like that, she was gone. I didn't see how I could ever step down from that bed in my hotel room and do whatever needed doing.

[In 2006 Robert Edward Maxfield pleaded no contest to the shooting death and was sentenced to 15 years.]

Still depressed by Tunde's death and struggling with a knee injury, Serena was knocked out of tennis for more than six months in 2006. Then came the magical 2007 Australian Open, which she improbably won after gutting out a tough third-round match.

I'd been away from the game for so long it felt like I was relaunching myself—Serena version 2.0. This version had a few glitches, to go along with a few extra pounds. As you might imagine, I ate a lot during that period in L.A. when I wasn't playing. There was a place called Stan's Donuts that just about did me in. And I wasn't doing any training (unless you count shopping on Rodeo Drive), so those calories had nowhere to go but my hips and thighs.

The tennis press was only too happy to point this out when I turned up in Melbourne for the Open. I tried to smile and press on. I was pumped to jump-start my career, but I was seriously out of shape and nowhere in the rankings. "It's simple," Venus had said [before the third round match against Nadia Petrova]. "Just look at the ball, and it'll come." But in the first set, it wasn't coming. In the second set, it still wasn't coming.

And then, finally, it did. There was one point when I let out this unbelievable grunt. You could hear it outside the stadium, someone told me. It was just a release, for all that pressure I was feeling. The pressure I put on myself. The pressure from my sponsors. The pressure from being away from the game all this time. I was still two points from losing, but I knew the match was mine. I would prove everyone wrong, and prove something to myself. That I was back where I belonged. I was determined to win, but not for those jerks at the newspaper, or for the sponsors who wanted nothing to do with me. No, I would do it for me. For the first time in my career, it hit me: that's why I was playing, after all.

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