(CNN) -- At times it was almost painful to watch. At one end of the court the world's No. 1 female tennis star playing well within herself; at the other her sister, a long way away from regaining that form and status. "Venus has had a great week, and honestly, if she hadn't had to play so many matches, it would have been a much tougher match," Serena Williams said after comfortably beating her older sibling on Saturday to reach the final of the Family Circle Cup in Charleston. The 31-year-old was slightly overstating the rigors of the competition in South Carolina, a tournament that heralded the formation of the women's tour back in 1973 but has this week attracted just two of the world's top-10 players.
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Serena Williams beats older sister Venus to reach Family Circle Cup final
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World No. 1 triumphs in less than an hour as she continues title defense
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Williams will next play former top-ranked player Jelena Jankovic
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Davis Cup champions Czech Republic lose doubles in Kazakhstan
Serena Williams
Serena Williams
Williams
Both Williams sisters won two matches on Friday to set up their first meeting since 2009, but it was defending champion @placeholder who looked the least affected as she won 6-1 6-2 in just 54 minutes.