NEW YORK (Reuters) - Venus Williams could stand in the way of younger sister Serena's bid for a calendar-year Grand Slam after reaching the quarter-finals of the U.S. Open with a 6-2 6-1 rout of Estonian teenager Anett Kontaveit on Sunday.
Seven-times grand slam winner Venus would face top-seeded world number one Serena in the last eight, should the three-times defending U.S. Open champion win her fourth-round match against fellow American Madison Keys.
The 35-year-old Venus, seeded 23rd, overpowered 19-year-old qualifier Kontaveit, winning 84 percent of her first serves, breaking the Estonian four times and making only nine unforced errors in the 50-minute match.
Serena, 33, who was following Venus onto the Arthur Ashe Stadium court, is trying to become the fourth woman to sweep all four grand slam singles titles in the same year after winning the Australian Open, French Open and Wimbledon this season.
Editing by Andrew Both