HIGHLIGHTS-Tennis-U.S. Open day four

The 22nd seed will next face Greek 15th seed Maria Sakkari. 1235 MUGURUZA UPSET BY UNSEEDED PIRONKOVA IN STRAIGHT SETS Spain's 10th seed Garbine Muguruza was knocked out 7-5 6-3 by unranked Bulgarian Tsvetana Pironkova in the second round. Playing in her first tournament in over three years following a maternity break, Pironkova won an overwhelming 93% of her first serve points, breaking the twice Grand Slam champion three times.

Highlights of the fourth day at the U.S. Open in New York on Thursday. The Grand Slam is being played without spectators due to the COVID-19 pandemic. (Times ET; GMT-4): 1307 ANISIMOVA WINS BATTLE OF AMERICAN TEENS

Amanda Anisimova, 19, fought back from a set down against 16-year-old Katrina Scott to advance to the third round with a 4-6 6-4 6-1 victory over her fellow American. Scott, making her Grand Slam debut, raced into a one-set lead on the back of her booming serve before Anisimova took control at 4-4 in the second set. The 22nd seed will next face Greek 15th seed Maria Sakkari.

1235 MUGURUZA UPSET BY UNSEEDED PIRONKOVA IN STRAIGHT SETS Spain's 10th seed Garbine Muguruza was knocked out 7-5 6-3 by unranked Bulgarian Tsvetana Pironkova in the second round.

Playing in her first tournament in over three years following a maternity break, Pironkova won an overwhelming 93% of her first serve points, breaking the twice Grand Slam champion three times. Ons Jabeur of Tunisia, seeded 27th, beat Estonia's Kaia Kanepi 7-6(8) 6-0 to move into the third round.

1109 PLAY UNDERWAY AT FLUSHING MEADOWS Play began in bright sunshine in New York with the temperature hovering around 26 degrees Celsius (78.8°F), with an expected high of 31 degrees.

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