Williams next gets former No. 1 Karolina Pliskova of the Czech Republic, the last woman to beat her at the U.S. Open, in the semifinals in 2016. Williams extended her head-to-head record against the Estonian to 5-0, despite dropping her first set against her opponent in their five meetings.
Kaepernick and Reid, two former San Francisco 49ers now out of the league, were each given huge ovations when they were introduced and shown on the big screen during the match between Serena and Venus Williams at the U.S. Open on Friday night.
Williams said that everyone should "be completely grateful and honored" at how both men have done so much for the "greater good". The American would win the next two games, but she couldn't find another break and after fighting off two set points saw Kanepi knot the match on her third chance.
In the decider, Williams took an early 2-0 lead and held on to reach the quarters.
Williams was already pregnant when she won her most recent Grand Slam title, at the 2017 Australian Open. Kanepi drilled aggressive winners, looked nearly untouchable off the forehand side despite Serena broke back to 5-3, and managed to win her first set ever against her as Serena missed a return just wide.
Williams reached the quarterfinals at Flushing Meadows for a 10th consecutive appearance - she wasn't there previous year because she gave birth to her daughter during the tournament - by picking her level up after a lull and using 18 aces to beat Kaia Kanepi of Estonia 6-0, 4-6, 6-3. She returned to Grand Slam tennis at the French Open in May, withdrawing before a fourth-round match with Maria Sharapova due to a pectoral muscle injury.More news: England youngsters need to play in Premier League - Southgate
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"That desire has not gone down at all", she said. "I think that was a great point".
Defending champion Sloane Stephens, the third seed, eased past Elise Mertens 6-3, 6-3 to book a quarter-final rematch with Latvian Anastasija Sevastova.
She added: "They really use their platform in ways that are really unfathomable".
She then reached the Wimbledon final in July but lost to Germany's Angelique Kerber. "Coming back from a baby is really hard, harder than I thought".
She continued: 'For the first time, I finally understand the concept of self-love and self-care. "That was the most important thing for me to improve, being fit and able to play long matches".
That day, Pliskova became a member of the illustrious club of 10 women, only three of whom are still active, who have ever defeated Williams at the U.S. Open, joining names such as Clijsters, Henin, Capriati, Davenport and the other Williams. "I'm kind of enjoying that, to be honest". "Wouldn't you love to see one of these National Football League owners, when somebody disrespects our flag, to say, 'Get that son of a bitch off the field right now. Out!"