Defending champion Gauff knocked out of US Open fourth round by Navarro

Defending champion Coco Gauff crashed out of the fourth round of the U.S. Open with a 6-3 4-6 6-3 loss to fellow American Emma Navarro in New York on Sunday.
Third-seeded Gauff was let down by her serve, producing 19 double faults, as Navarro, who knocked Gauff out of Wimbledon in July, reached the quarter-finals of the year’s last major.