Barty, Serena on US Open collision course
ASHLEIGH Barty has passed the sternest test yet of her US Open title credentials to equal her best run in New York.
Barty delivered a serving masterclass class on Friday (local time) to reach the last 16 for the second straight year with a composed 7-5 6-3 victory over rising Greek Maria Sakkari.
Sakkari, seeded 30th, had beaten Barty last year in Indian Wells but Australia's world No.2 played the match on her terms from the outset.
The French Open champion fired down 10 aces and dropped serve only once while breaking Sakkari four times during the 87-minute work-out on Louis Armstrong Stadium.
"This is an incredible court. New York is an incredible city and last year I felt like an adopted American playing with Coco (Vandeweghe) in the doubles, so I'm glad you haven't forgotten," Barty said after enjoying clear crowd favouritism during the match.
"Maria is an incredible competitor, a great mover around the court and plays her best tennis when she's on the move and so it was important for me to try and dictate without going into her patterns.
"It's tricky to play a friend but I was really happy with the way I able to close out those two sets."
Barty will face either China's 18th seed Qiang Wang or unseeded Frenchwoman Fiona Ferro next on Sunday.
Williams moved another step closer to a record-tying 24th career Grand Slam title with a comfortable 6-3 6-2 victory over Czech Karolina Muchova to reach the last 16.
Wimbledon quarter-finalist Muchova held serve for an early 3-2 lead in her first career meeting with Williams, but the six-time champion cranked up the pace and won the next seven games to take over the match.
Williams and Barty will likely clash in the quarter finals.
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