Serena Williams raced to a 6-2 6-1 victory over sister Venus to progress to the fourth round of the US Open.

There will be further tests to come that will show whether Serena is totally back to her best, but there was little to fault as she won in just 71 minutes, equalling the most one-sided match in their long history.

The sisters shared an embrace at the net before a muted wave to the crowd from Serena, who will next face Estonia's Kaia Kanepi.

"It's not easy," said the 36-year-old. "She's my best friend, she means the world to me and she's so supportive of my career and I'm extremely supportive of her career.

"Every time she loses I feel like I lose. I love her with all my heart and she's the only reason I'm still out here. I owe everything to her."

Serena rated it her best performance since returning to the tour in March but Venus went a step further, declaring this Serena's best ever display against her.

The score matched Serena's victory in Charleston five years ago while the loser had always won at least six games in their 15 previous Grand Slam meetings. Serena now leads the overall head-to-head 18-12 and has won nine of their last 11 clashes.

Sky Sports

BDST: 1655 HRS, SEPT 1, 2018
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