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Serena Williams defeated her older sister, Venus, in three sets in the U.S. Open quarterfinals on Tuesday.
The final score was 6-3, 1-6, 6-3. Serena, 33, will advance to the tournament's semifinals, where she will face Roberta Vinci of Italy. She is now just two victories away from becoming the first tennis player -- male or female -- to win all four major annual tennis tournaments in the same year since 1988, when Steffi Graf achieved the feat.