Media playback is not supported on this device US Open: Top-ranked Barty stunned in second round
US Open Venue: Flushing Meadows, New York Dates: 27 August-9 September Coverage: Live radio coverage on BBC Radio 5 live sports extra; live text commentaries on the BBC Sport website
World number two Ashleigh Barty was knocked out in the second round of the US Open by Chinese qualifier Zhang Shuai, going down 7-6 (7-5) 7-6 (7-5).
The 23-year-old Barty could not catch up in the tie-break in New York, with Zhang winning four consecutive points.
Australian Barty was a finalist at Flushing Meadows 12 months ago.
Barty was seen crying during the match and later said she “cried a lot” because her ranking “stopped moving in the right direction” in recent weeks.
The defeat means Barty’s time at the top of the rankings ended at four weeks.
Earlier in the tournament, British number two Aljaz Bedene was knocked out in the first round by Steve Johnson.
On Friday, reigning US Open champion Sloane Stephens also suffered a shock exit as she was beaten by unseeded Australian qualifier Arina Rodionova.
Barty has dropped out of the top 20 since reaching the final in New York last year,
She began her final serve of 2017 on 5-3 up in the opening set and immediately went to 30-0 in the tie-break before Zhang won four points in a row to take the set.
Barty raised her level again to secure the first point of the second set before Zhang took control.
The Chinese needed to save a break point at 5-5 to secure the set tie-break before clinching it 7-5.
Barty had five break points in the second set but failed to convert any of them, while Zhang secured eight winners to keep alive her hopes of becoming the first Chinese woman to reach the US Open last four.
“What an incredible job Zhang Shuai has done,” said BBC tennis correspondent Russell Fuller.
“She starts with a lot of confidence after winning in Mallorca. A missed first serve on match point proves fatal for the Australian.
“More significant is the career-defining moment for Halep, who takes her place in a final for the first time, partnering Federer in doubles next week.”
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