Venus Williams defeats Caroline Wozniacki at Miami Open

Basking in her latest victory Monday, a beaming Venus Williams stood near her changeover chair launching autographed balls into the stands, steering her shots with body English and applauding the fans who scrambled for the souvenirs.

For Williams, tennis is still fun. She’s 34 but on the rise in the rankings, and she beat former No. 1 Caroline Wozniacki 6-3, 7-6 (1) Monday to reach the Miami Open quarterfinals.

Williams is a three-time Key Biscayne champion, but her most recent title came in 2001. Seeded 16th, she’s into the quarterfinals at the tournament for the first time since 2012.

“Tennis has always been a blast,” Williams said. “But, you know, I’m feeling good out there.”

She could meet her sister Serena in the final. Serena, who has won the tournament a record seven times, advanced by beating 2006 champion Svetlana Kuznetsova 6-2, 6-3.

In men’s third-round play, No. 4 Kei Nishikori beat No. 32 Viktor Troicki 6-2, 6-2.

While Serena, 33, has been ranked No. 1 for the past two years, Venus’ fortunes are only lately on the upswing after health issues caused a long slump that stirred retirement speculation. In January at the Australian Open, she reached her first Grand Slam quarterfinal in five years before losing, and with the victory over Wozniacki, she’s 4-0 in 2015 against top-10 players.

“I don’t give up, and I believe in myself no matter what the odds are and what you may experience,” she said. “I have always seen it as something to overcome, and not something that could stop me.”

Unlike her sister, she has never tired of tennis, a problem for some top players even before their skills decline.

“I never get bored, actually,” Venus said. “Tennis is definitely not pushing paper. I mean, when you get out there you have no idea what’s going to happen in the point. You can try to plan it the best you can, but it’s all up in the air. You have to improvise every single time. That never gets boring.”