Serena Williams beat Madison Keys by 6-3 6-3 to set up a quarter-final against her sister Venus. They will face for the 4th time in US Open. Serena Williams, who is hoping to win her first Grand Slam victory over Madison Key at the US Open.Serena, 33, is now three wins away from her first calendar Grand Slam since Steffi Graf in 1988.

Williams said afterwards, “I served much better today. I’m so proud I was able to serve better. Obviously I had to – I knew I wouldn’t have too many chances to break.”

Novak Djokovic defeated Roberto Bautista Agut by 6-3 4-6 6-4 6-3 in the fourth round of US Open.
Djokovic has already won the Australian Open and Wimbledon this season. Now he’ll Feliciano Lopez in the next round.

Men’s defending champion Marin Cilic will meet 19th seed Jo-Wilfried Tsonga in the last eight. Marin defeated J. Chardy 6-3 2-6 7-6 (7-2) 6-1 in the fourth round of US Open 2015.
M. Cilic said, “Jeremy played really well from second set on and I was having trouble with my movement after twisting my ankle.”