It was a pleasant day in New York weather-wise, and so it was for the favorites as the first week of the tournament came to an end.

Williams Sisters to Clash after Victories

Both Serena and Venus Williams played high-quality tennis on Sunday and will now square off against each other in the quarterfinals.

Top-seeded Serena easily played her best match of the tournament in an impressive 6-3, 6-3 win against fellow American Madison Keys. The serving woes of previous matches were a distant memory after Williams served efficiently against the big hitter. Williams won 79 percent of her first-serve points in the match, including six aces with no double faults.

It was a clean performance by the world No. 1, who only gave away six unforced errors in the match, while her counterpart yielded 19. Meanwhile, Williams would attack the Keys second serve, which produced a high level of success. Keys would only win 39 percent of those points.

Meanwhile, older sister Venus was sharp as well in a 6-2, 6-1 victory against Anett Kontaveit of Estonia. Williams broke serve twice in the first set and ran to a 5-0 lead in the second before the 19-year old would scratch the scoreboard. Twenty-one unforced errors and struggles on her second serve were more than Kontaveit could overcome.

When the draw was released, many anticipated that Serena’s journey to history might ultimately go through her sister. Now, as she attempts to equal Steffi Graf with 22 major championships and to complete a calendar-year Grand Slam, Serena will need to defeat a veteran against whom she holds a 15-11 career edge. In their last meeting, Serena won a straightforward 6-4, 6-3 match in the round of 16 at Wimbledon earlier this year. Venus last defeated her sister at the Canadian Masters in 2014.

When asked about her history in matches against her sister, Venus responded, “It's been awesome, I'm so proud of Serena, and I think she's proud of me. We inspire each other.” Meanwhile, Serena attempted to keep their meeting in perspective. “At least there will be one Williams in the semifinals,” she said.

Djokovic overcomes tough test

In a match that appeared to be a routine win for the top seed early, Roberto Bautista-Agut elevated his game, fought tooth-and-nail, and pushed the nine-time champion in a fantastic four-setter. But it was Novak Djokovic prevailing, 6-3, 4-6, 6-4, 6-3.

It looked like business as usual for Djokovic as the first set unfolded. Bautista-Agut would play strong tennis, but the world No. 1 would capture the key points to swing the set in his favor. But the Spaniard had other ideas in the second set, after the Serb gained an early break advantage. Behind the strength of his big, flat forehand, the 23rd seed would drive Djokovic deep in the court and would tilt the set in his favor. To the ooh’s and ah’s of the crowd, Bautista-Agut consistently ripped lethal forehands and would break Djokovic twice down the stretch, which was enough to close out the set and even the match.

But as great champions often do, Djokovic would find just enough to turn the momentum in his favor. In the case, it was ever so slightly, for Bautista-Agut fought to the very end. However, it was not enough, and Djokovic would hold on to win the last two sets and advance to the quarterfinals, where he will face Feliciano Lopez.

Defending Champion Moves On

Despite tweaking his ankle, ninth-seeded Marin Cilic played quality tennis in his 6-3, 2-6, 7-6, 6-1 win against Jeremy Chardy in an early match on Ashe Stadium.

The defending U. S. Open champion put forward a strong first set behind his consistent serve and took advantage of a weak service game by the Frenchman to take the opener. But after rolling his ankle in the second set, Cilic appeared to lose some mobility temporarily, and it cost him as Chardy took advantage. He would quickly even the match.

However, the Croat would rebound, and in a competitive third set where neither could make a dent in his opponent’s serve, he would take it after a 7-2 tiebreak score. That result seemed to put Chardy on his heels in the fourth set, which Cilic would roll through with ease.

Cilic addressed his ankle injury after the match. “The first couple of games after that were not easy. I was conscious of it,” he admitted. “But after that I didn’t have any trouble at all. I played really good in the fourth set. I didn’t lose too much energy here today. I’m going to try to keep my streak going for a couple more matches.”

Cilic has won his last 11 matches at Flushing Meadows and will have a day off to rest his ankle before he faces Jo-Wilfried Tsonga in the quarterfinals.

News and Notes

It was an unfortunate end to Eugenie Bouchard’s tournament when she was forced to withdraw from competition after she slipped and fell in the locker room on Friday night. The Canadian pulled out of doubles and mixed doubles on Saturday but had hoped to play singles on Sunday. However, her head injury would not allow it, and she entered the grounds clearly not in condition to play a match.

Bouchard had shown glimpses of a level of play that led to a breakout season in 2014 during the tournament and had hoped to salvage a difficult and frustrating season this year.