NEW YORK — No reason for any extra practice after this performance by Serena Williams.
Playing the best she has during this U.S. Open as she chases a calendar-year Grand Slam, Williams set up a quarterfinal against older sister Venus by making only six unforced errors in a 6-3, 6-3 victory over 19th-seeded Madison Keys on Sunday.
Serena took only 68 minutes to dismiss Keys, a 20-year-old American with formidable serves and forehands who simply was outplayed.
Already a winner of the past four major tournaments, including last year’s U.S. Open, Serena is trying to become the first tennis player to win all four in the same season since Steffi Graf in 1988.
Asked why it’s been so long since anyone else pulled off a true Grand Slam, Serena paused for effect, smiled and answered: “I don’t know why it took me so long.”
Standing in the way at the moment is Venus. This will be the 27th all-Williams match over their long and successful careers, and Serena leads 15-11, including 8-5 at majors.
Venus, the oldest woman in the tournament at 35, was on court even less time than her sibling on Sunday, overwhelming 19-year-old qualifier Anett Kontaveit of Estonia 6-2, 6-1 in 50 minutes.
Another women’s fourth-round match scheduled for Sunday was scratched when 25th-seeded Eugenie Bouchard withdrew with a concussion, two days after slipping and falling in the locker room. That allowed Roberta Vinci of Italy to advance to the quarterfinals.
Two men’s matchups in the round of eight are set: No. 1 Novak Djokovic vs. No. 18 Feliciano Lopez, and defending champion Marin Cilic vs. No. 19 Jo-Wilfried Tsonga.
Djokovic lost a set for the first time this tournament, and he responded by stomping on a racket while it leaned on his red bag next to a changeover chair, earning a warning from the chair umpire. But he reached the quarterfinals at a 26th consecutive major by beating 23rd-seeded Roberto Bautista Agut 6-3, 4-6, 6-4, 6-3 at night.
Thumbnail photo via Robert Deutsch/USA TODAY Sports Images
Thumbnail photo via Serena Williams of the USA hits autographed balls to the crowd after beating Madison Keys of the USA on day seven of the 2015 U.S. Open tennis tournament at USTA Billie Jean King National Tennis Center.