KEY BISCAYNE (AP) — Venus Williams is working on a book and her left-handed serve.  She’s preparing to host the Williams Invitational for family and an NFL player. She loves her new role as NFL team owner with a small stake in the Miami Dolphins.

Despite her typically spotty attendance on the WTA Tour, Williams is as busy as ever. And now she's ready for a tournament.

Williams seeks her fourth Key Biscayne title – but her first since 2001 – in the Sony Ericsson Open. While play began on Tuesday, seeded players had first-round byes, and Williams' opening match was scheduled for Thursday against Sorana Cirstea of Romania.

“It's nice to play at home,” said Williams, who lives a 90-minute drive north in Palm Beach Gardens.  “There's so much support from the crowd, and so much friends and family look forward to watching me play.”

The cheering section will include her sister, five-time champion Serena Williams, who withdrew last week because of the left knee injury that has sidelined her since she won the Australian Open in January.

“I can still swing my racket pretty well in her memory,” Venus said.

Not left-handed, though. She has practiced with her off hand in preparation for some private doubles with Serena, at least one other sister, their mother and Minnesota Vikings tackle Bryant McKinnie.  He’s a friend and tennis novice looking for a match, and the date and location will be determined later.

“It's called the Williams Invitational,” Venus said. “I'm playing left-handed so it evens the field. My forehand is pretty mean. My serve is nonexistent, and my backhand is horrible.”

Playing right-handed, Venus lost in the quarterfinals in Australia and has gone 10-0 since, winning titles in Dubai and Acapulco in February. She struggled with a troublesome left knee last year, when she reached the final eight at only one Grand Slam event. But she said she's healthy and looking forward to a big year at age 29.

Ranked fifth, she’s the oldest player in the top 40.

“Serena and I have done some great career planning and are playing at the peak of our tennis right now,” Venus said. “Tennis has been a sport where you play this insane schedule from 14 years old, and at 26 it's over. We've paced ourselves to play great tennis as long as we want.”

To the annoyance of tennis traditionalists, the sisters have always found plenty of diversions. They branched out into a new sport last year, buying a small stake in the Dolphins, and enjoyed the associated perks when the Super Bowl came to Miami in February.

“I don't think it really sank in until we went to one of the owners’ meetings during the Super Bowl and we were like, ‘Hey, we're in the door,’ ” Venus said. “It was pretty exciting and beyond our dreams.”

Her newest role is as an interviewer. For the upcoming book “Come to Win,”  she talked with such successful people as Bill Clinton, Condoleezza Rice and Vera Wang about the role sports played in their lives.

“I don’t get very nervous, but for some of the interviews I'm like, ‘Am I going to get in all the questions I need? I hope we can get through all the material. Are they going to hang up after five minutes?’ ”

The book is due out in June – Wimbledon time. Venus was runner-up to Serena there last year, and Serena also won when they met in the Key Biscayne semifinals a year ago.

Serena's injury leaves no chance for a rematch, while creating an opportunity for the rest of the field.

“It's open,” second-ranked Caroline Wozniacki said. “A lot of players have the possibility to win.  It's just about who has the best two weeks.”

It's also about whether anyone can eliminate Venus. More than a decade into their careers, the Williams sisters remain the players to beat wherever they go.

That's despite the recent waves created by a new generation of players, including Wozniacki and defending Key Biscayne champion Victoria Azar-enka, and despite comebacks by Grand Slam champs Justine Henin and Kim Clijsters.

While Serena is ranked No. 1, Venus is the tour's hot player, and she chuckles when asked about her goal for 2010.

“Win, win, win, win, win, win, win,” she said.

That’s seven wins. She'll only need six to claim the Key Biscayne title.