Serena Williams will meet sister Venus in the U.S. Open quarterfinals, thanks to their Sunday match victories at Flushing Meadows.
Coming off her first three-set match of the tournament, Serena dispatched rising American Madison Keys 6-3, 6-3. Hours earlier, Venus delivered another strong performance by beating Estonia's Anett Kontaveit 6-2, 6-1. Keys was seeded 19th; Kontaveit was a qualifier.
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The sisters aren't strangers in competition, including head-to-head championship matches in major tournaments. Serena, 33, leads their all-time series 15-11, including a 6-2 edge in grand slam events.
Serena is seeking a true grand slam and must win the Open to become the first player since Steffi Graf in 1998 to hold do so. She started her run by winning the Open last year.
Venus won the Open in 2000 and 2001. Her most recent major title was Wimbledon in 2008.
Keys applied early pressure but Serena delivered winners and aces in response. At 20, this was Keys' deepest run in the major. But Serena hit stride early in the match after a series of slow starts. He match lasted 68 minutes.
Venus needed 52 minutes to dispatch Kontaveit. Now she faces Serena and her potent serve.
Rally, winner and the early lead for #Venus. #usopen @Chase http://t.co/jC35E2I8Hs
— US Open Tennis (@usopen) September 6, 2015"She's playing great," Serena said of Venus. "I barely had time to get ready for my match because she won so fast. I have to be ready for that.
"At least a Williams will be in the semis, so that's good."
Venus also had praise for her sister. "I'm so proud of Serena, and I think she's proud of me," she said. "We inspire each other."
A Williams vs. Williams match will be a boost for the Open, which saw Canadian idol Eugenie Bouchard withdraw on Sunday because of a concussion. Second seed Simona Halep continues her course toward the finals, but the tournament began without marquee player Maria Sharapova and lost another with Caroline Wozniacki lost early.