• Serena Williams beat her sister Venus in their 30th professional match to reach the fourth round of the U.S. Open.

• Last year’s men’s singles finalists, Rafael Nadal and Kevin Anderson, survived challenges from young rising stars.

• Sloane Stephens, the highest seed left in the women’s draw, earned a spot in the fourth round with a win over Victoria Azarenka.

• The chair umpire who had a heart-to-heart talk with Nick Kyrgios during his match on Thursday “went beyond protocol,” the U.S.T.A. said, but will be allowed to keep working at the tournament.