World number one Serena Williams will resume her bid for a calendar-year Grand Slam as she tries to recover from a poor serving performance to reach the fourth round of the US Open on Friday, while men's top seed Novak Djokovic and two-time champion Rafael Nadal also seek to cement their spots in the round of 16.
Three-time defending champion Williams has won her past 30 Grand Slam matches, completing her second 'Serena Slam' by taking four major titles in a row, and could add to her legend even more in the Flushing Meadows fortnight. The 33-year-old American, who faces compatriot Bethanie Mattek-Sands in a third-round night match at Arthur Ashe Stadium, could complete the first calendar Grand Slam since Steffi Graf in 1988.
Williams would also collect her 22nd career Grand Slam singles crown, matching Graf's Open Era record and moving two shy of equaling Australian Margaret Court's all-time record.
But first she has to get past Mattek-Sands, who shared two Grand Slam doubles titles this year. "Knowing that she's capable of having big wins kind of relaxes me because I know she's going to come out and I know what to expect," Williams said.
"She's going to give 300 percent. She's a huge fighter. She has a great game. I have to start out strong if I want to stay in the tournament. If not, I can go on vacation."
Williams must also calm the nerves that overwhelmed her at moments in the second round. "I'm going to get back into the place that I was and I'll be fine again," Williams vowed. The highest-ranked rival on her side of the draw, 12th-seeded Swiss teenager Belinda Bencic, will face Serena's older sister, seven-time Grand Slam singles champion Venus Williams, in another third-round encounter at Ashe. The winner could face Serena Williams in the quarter-finals.
World number one Djokovic, seeking his third Grand Slam title of the year and his fifth US Open final in six attempts, meets Italian 25th seed Andreas Seppi for a place in the fourth round. The Serbian star would also have been seeking a calendar Slam sweep of his own had he not lost the French Open final to Swiss Stan Wawrinka.
Spanish eighth seed Nadal, a 14-time Grand Slam champion, meets Italian 32nd seed Fabio Fognini for a spot in the last 16. He and Djokovic are on a collision course for a quarter-final showdown. Nadal and Fognini have played thrice this year, with Fognini winning two, at the Rio Open and in Barcelona, but the Spaniard won their most recent encounter in the Hamburg Open final, a match that saw tensions between the two flaring as the Italian accused Nadal of hampering his pace of serving and pointed a finger at the Spaniard during a changeover.
Defending champion Maric Cilic, the ninth seed from Croatia, and Spanish seventh seed David Ferrer could book a fourth-round meeting with victories on Friday. Cilic faces Kazakhstan's Mikhail Kukushkin while Ferrer takes on 27th-seeded Frenchman Jeremy Chardy.
Slightly cooler conditions were predicted than the past four days, during which sweltering heat and humidity have produced a Grand Slam record 12 men's retirements during matches and two more on the women's side.