Sister showdowns not new for tennis superstars Venus and Serena

QUEENS, N.Y. -- Serena Williams topped her sister Venus at the U.S. Open Tuesday night in their 27th meeting; 6-2, 1-6, 6-3 advancing to the semifinals and moving two wins from a Grand Slam.

In many parts of America, Tuesday felt more like July than September.

It's not exactly tennis weather, though it's fitting perhaps, as the hottest rivalry in tennis is renewed on Tuesday night at the U.S. Open in New York.

Fourteen years ago to the day, Serena and Venus Williams faced off in the U.S. Open finals for the first time, a dream sibling matchup the younger sister predicted when she was still in braces.

"If you want to be the best that you want to do in your own sport, then you have to prepare for this type of attention," Serena said in 1998.

In 2001, Venus was on top. Now Serena's the top seed, and vying for the sport's Grand Slam -- to win all four major tournaments in one year. The one person standing in her way? Her sister.

"I think no one's out to be a spoiler, but at the same time you are focused on winning your match even though the circumstances are really much different than usual," said Venus.

"For me, she's the only player in the draw I don't want to play, not only because she's my sister, but for me she's the best player," said Serena.

Even though it's happened 26 times, their parents still can't bear to watch. Their mother went sightseeing at the precise moment her daughters were playing at Wimbledon this summer.

Serena has won 15 of their last 26 matches, but the elder Williams has beaten her baby sister more than any other player in the tournament.

Tennis legend Billie Jean King has followed their entire career.

"I think either way it would be unbelievable," she said.

Venus and Serena currently hold 28 major titles between them.