Serena Williams on Friday night defeated her older sister Venus Williams to reach the US Open fourth round in New York.
The 23-time Grand Slam champion, looking to equal Margaret Court’s all-time record of 24, needed just 71 minutes to win 6-1 6-2.
The American siblings, aged 38 and 36, were playing for the 30th time – but it was not much of a contest.
Serena Williams, who had a medical timeout in the first set, will play Estonia’s Kaia Kanepi in the last 16.
Kanepi, 33, dumped world number one Simona Halep out in the first round and has not dropped a set so far at Flushing Meadows.
“This was my best match since I have returned,” said Serena, who had time out of the game to give birth to her daughter last September.
By dropping just three games, Serena earned her joint biggest victory over Venus, alongside her 6-1 6-2 win at Charleston in 2013.
Venus said she thought it was her sister’s best performance in their matches, because she did not “even get to really touch any balls”.
“I don’t think I did a lot wrong. But she just did everything right,” Venus told a news conference.
“Obviously, that level is definitely where she’s going to want to stay during this whole tournament.”
The Williams sisters played each other for the first time in the second round of the 1998 Australian Open, when a 17-year-old Venus defeated a 16-year-old Serena in straight sets, 7-6 (4), 6-1.
Friday night was their milestone 30th career meeting. Although Venus dominated the series early on, winning five of their first six meetings between 1998 and 2001, Serena has won 16 of their 23 meetings since then—including eight of their last 10—to build a 17-12 overall head-to-head lead.
Serena’s 10-5 lead in Grand Slam meetings includes a 2-1 record at the Australian Open, a 1-0 record at the French Open, 4-2 at Wimbledon and 3-2 at the US Open. She lost their first meeting here in the 2001 final, but won three of their last four, most recently in the 2015 quarterfinals.