New York - Defending champion Serena Williams won her much-anticipated US Open showdown with Sloane Stephens on Sunday while Li Na avenged a painful loss in Rome to join the world number one in the last eight.
Williams defeated US 15th seed Sloane Stephens 6-4, 6-1 to reach the US Open quarter-finals, winning eight of the last nine game in avenging a loss that ousted her from the 2013 Australian Open.
"It definitely felt like a bigger match because Sloane is such a great player, but I had to stay focused in the moment," Williams said. "I just tried the whole time to do what I wanted to, stay calm and stay relaxed."
Williams booked a quarter-final against Spanish 18th seed Carla Suarez Navarro, who upset German eighth seed Angelique Kerber 4-6, 6-3, 7-6 (7/3).