Serena Williams came from behind to beat her sister, Venus Williams to reach the quarter-finals of the Top Seed Open.
The former number one came from a set down to beat her equally legendary sister 3-6 6-3 6-4 on Thursday August 13.
Serena also trailed 4-2 in the deciding set but claimed four straight games to win a high-quality match in Kentucky.
This is the 31st competitive singles match between the sisters, with Serena winning 19 times and Venus, 12.
Serena broke seven-time Grand Slam champion Venus, 40, in the first game of the match but faded to lose the first set 6-3 in 41 minutes, before taking the second by the same score in 50 minutes.
The 38-year-old broke first in the final set but Venus fought back and looked to be on course for victory at 4-2 up.
However, hit some crucial winners to reach the last eight of her first tournament in six months.
“I honestly don’t know how I was able to pull it out at the end,” said 23-time Grand Slam champion Serena.
“I have been losing a lot of those tight sets so I said to myself that I really needed to win, just for my game and my confidence.”
Serena will face either fellow American Shelby Rogers or Canadian Leylah Annie Fernandez in the quarter-finals of the behind-closed-doors event.
“I didn’t come here to win for the first time in my career, I just came here to get some matches and see what happens,” added Serena, who is preparing to play in this year’s US Open, which starts on 31 August.
Her chances of winning the US Open title has been significantly boosted as several top seeds have opted to pull out of the tournament over coronavirus fears.
This includes Women’s defending champion Bianca Andreescu, who became the latest to pull out on Thursday.
Andreescu won the US Open title last year after beating Serena Williams.