Coco Gauff ousted by Emma Navarro in US Open fourth round
NEW YORK, Sept 1 (Reuters) - Defending champion Coco Gauff became the latest big-name casualty to exit the U.S. Open when Emma Navarro won their fourth round match 6-3 4-6 6-3 to down her stunned American compatriot for the second time in a Grand Slam this year.