Serena Williams retained the No. 1 world ranking by being her sister Venus 6-4, 3-6, 6-3 in the semi-finals of the Sony Ericsson Open on Thursday.
The match was the 20th meeting between the sisters, and each has won 10 times.
Serena needed to reach the final to retain the top ranking she has held since Feb. 2. Otherwise she would have been supplanted next week by No. 2-ranked Dinara Safina of Russia.
“I’m excited,” Serena said. “I was thinking I’d love to remain No. 1. I think I was more happy about that than winning the match.”
Serena’s opponent today will be 19-year-old Victoria Azarenka of Belarus, who beat 2006 champion Svetlana Kuznetsova 6-3, 2-6, 7-5. Azarenka became ill with a stomach complaint before losing a fourth-round match against Williams at the Australian Open in January.
Serena jumped to a 4-1 lead in the final set against her older sister and broke serve for the sixth time in the final game. When she closed out her victory, she hopped in delight, raised a fist and shouted “Yes!” She then met her sister at the net with a handshake and slap on the back.
“Even though she’s my sister, I’m still here to win,” Venus said. “I can’t give anyone anything. So I’m disappointed that I lost tonight, whether or not she kept the ranking or not.”
Top-ranked Rafael Nadal lost in the men’s quarter-finals to 20-year-old Argentine Juan Martin del Potro, 6-4, 3-6, 7-6 (3).
Nadal had won all four of his previous meetings with del Potro without dropping a set — including a quarter-final victory at Indian Wells.
The upset delighted a partisan crowd that included many transplants from Argentina.
Del Potro had lost all nine sets in their four previous matches, but he was buoyed by a home-court advantage, with many transplanted Argentines in the crowd singing “Del-Po” between points.
“Wonderful for the crowd,” top-ranked Nadal said. “Terrible for me.”
The No. 6-seeded del Potro was yesterday to face No. 4 Andy Murray of Britain, who beat No. 8 Fernando Verdasco 6-1, 6-2.
Murray broke serve five times and saved seven of eight break points against him.
Serena is seeking her sixth Key Biscayne title, which would break the record she shares with Steffi Graf. She’s 52-5 in the event, with one loss since 2001 — to Venus.
After losing her past two meetings with Venus, Serena said she was glad to pull even in the rivalry.
“I would love to be in the lead again,” she said.
Del Potro showed patience in long rallies and used his looping forehand to keep Nadal deep as their three-hour match built to a dramatic finish.
“I beat him with my mind and with my game,” del Potro said. “When we played long points, I was dominating every time.”
Nadal was up two breaks in the final set at 3-love, but del Potro climbed back into the match by winning 12 of the next 14 points.
“I played really bad all the time,” Nadal said. “When I have it 3-love in the third, I played worse. It was amazing disaster.”
When Nadal lost serve for the second consecutive time for 3-all, del Potro let loose a primal scream. There was more noise to come.
In the 12th game of the set, Nadal saved three match points, two with aces. He caught a break in the tiebreaker when his return skipped along the net cord before clearing it for a winner and a 3-2 lead.
That was the last point Nadal won. Del Potro hit three consecutive winners to go up 6-3, and on the final point Nadal put a backhand in the net as the crowd erupted one last time.