NEW YORK, NY, USA - Former World No.1 Serena Williams put on a command performance to dispatch sister Venus in the 30th match of their historic rivalry, triumphing, 6-1, 6-2, to reach the second week of the US Open for the 17th time in her career.
"It feels good for the match to be over with," a relieved Serena said after the match. "Win or lose, it just feels good that that's done."
Playing in Flushing Meadows for the first time since marrying and giving birth to daughter Alexis Olympia Jr., Serena avenged the BNP Paribas Open loss to Venus that kicked off her comeback in March, playing pitch-perfect tennis to outlast her elder sister after 71 minutes on Arthur Ashe Stadium.
"It's definitely different now," she said of their rivalry. "I feel like we want it so bad now. I mean, we wanted it really bad when you were younger, but we had a lot more years in our future. Now, I mean, we definitely want to continue to play, but it's not like we're 18 and 19 any more. So it's a little bit different."
The highly-anticipated encounter was their first at the US Open in three years, when they faced off in the 2015 quarterfinals as Serena aimed to complete the elusive Calendar Year Grand Slam. After each held serve to start the match, Serena quickly caught fire, winning the next seven games to edge ahead a set and a break, even saving a break point early in the second set.
Venus, who reached the semifinals at this event last year - narrowly losing to eventual champion Sloane Stephens - interrupted her sister's momentum with a service hold, but Serena would not be denied on Friday night. She soon grabbed an insurance break and served out the victory shortly thereafter.
"I think it's the best match she's ever played against me," Venus said. "I don't think I did a lot wrong. But she just did everything right. Obviously that level is definitely where she's going to want to stay during this whole tournament.
"She didn't win that match tonight because I just rolled over. She played untouchable tennis. Whoever she plays, she's going to earn it. It's not like people don't try. People will try against her. I know people are going to keep that up."
In all, Serena struck a dazzling 34 winners to just 22 unforced errors - including 10 aces - and won a whopping 88% of points behind her first serve.
"For me it takes more mental energy than physical," Serena said. "It's not easy, but it is what it is. We started this journey 35 years ago, maybe less. Well, in a way, it started before we were born, so we started this journey a long time ago. We kind of knew what to expect. Even though it's difficult, especially for me, we just do the best that we can."
Up next for Serena is Estonian giant-killer Kaia Kanepi, who continued to back up her first round stunner over World No.1 Simona Halep with a straight-set win over Rebecca Peterson.
Serena and Kanepi last played at this very tournament in 2014, and is the six-time Grand Slam quarterfinalist' only defeat in a Round of 16 match at a major tournament.
"She obviously knows how to win. She played and beat the No.1 seed. I've played her a lot. We've had some close matches. Each match is new. She knows how to play very good tennis."