By Amy Tennery
NEW YORK (Reuters) - Japan's Naomi Osaka reached her first Grand Slam quarter-final by beating Aryna Sabalenka 6-3 2-6 6-4 in a pressure-packed clash of two hard-serving 20-year-old prospects.
Osaka, who won the Indian Wells Masters tournament in March, fired nine aces and produced 32 unforced errors, 10 fewer than her Belarussian opponent, in a gusty defensive performance.
Sabalenka, who saved three break points in the final set, flung her racket in dismay after committing a double-fault on match point, handing victory to her 19th-ranked opponent.
An emotional Osaka wiped tears from her eyes in an on-court interview, thanking the crowd and saying she would not have forgiven herself had she lost.
"I was just thinking I have to fight for every point; even if I break a leg I should try to get to every ball," she said.
Osaka next faces either unseeded Czech Marketa Vondrousova, who upset 13th seed Kiki Bertens in the third round, or Lesia Tsurenko of Ukraine, who were playing later in the Grandstand.
(Reporting by Amy Tennery; Editing by Ken Ferris)