The fourth day of the U.S. Open featured a number of top players in action, though none more legendary than Roger Federer, who had one of the more memorable matches on Thursday.
Below, we'll break down the day's results and top storylines.
Key Men's Results
Alexandr Dolgopolov def. (15) Tomas Berdych, 3-6, 6-1, 7-6, 6-2
(24) Juan Martin del Potro def. Adrian Menendez-Maceiras, 6-2, 6-3, 7-6
Andrey Rublev def. (7) Grigor Dimitrov, 7-5, 7-6, 6-3
(30) Adrian Mannarino def. Bjorn Fratangelo, 6-3, 6-7, 6-1, 6-2
(11) Roberto Bautista Agut def. Dustin Brown, 6-1, 6-3, 7-6
(31) Feliciano Lopez def. Fernando Verdasco, 6-3, 6-2, 3-6, 6-1
(3) Roger Federer def. Mikhail Youzhny 6-1, 6-7, 4-6, 6-4, 6-2
(1) Rafael Nadal def. Taro Daniel, 4-6, 6-3, 6-2, 6-2
For the day's full results be sure to check out USOpen.org.
Key Women's Results
(4) Elina Svitolina def. Evgeniya Rodina, 6-4, 6-4
Jennifer Brady def. (23) Barbora Strycova, 6-1, 6-1
(12) Jelena Ostapenko def. Sorana Cirstea, 6-4, 6-4
(1) Karolina Pliskova def. Nicole Gibbs, 2-6, 6-3, 6-4
Shelby Rogers def. (25) Daria Gavrilova, 7-6, 4-6, 7-6
(27) Zhang Shuai def. Risa Ozaki, 6-0, 6-3
(20) CoCo Vandeweghe def. Ons Jabeur, 7-6(6), 6-2
Kurumi Nara def. (8) Svetlana Kuznetsova, 6-3, 3-6, 6-3
For the day's full results, be sure to check out USOpen.org.
Despite dropping the second and third sets against Youzhny, he managed to sneak into the third round, though there is cause for concern, as he's needed all 10 sets to advance in his opening two matches.
For one of the favorites at this tournament, it's been a poor start, as Ben Rothenberg of the New York Times noted:
Ben Rothenberg @BenRothenberg
Federer served and hit forehands well, but hit just 7 backhand winners vs 35 backhand unforced errors. Will need to improve, quickly.#usopen2017-8-31 22:31:18
It's fair to question how much fuel Federer will have left in the tank after his grueling start to this tournament. And in the great pastiche of Federer's career, Tennis Channel analyst Jon Wertheim wasn't sure how to classify this match:
Jon Wertheim @jon_wertheim
"Bizarre Federer match" is not a common phrase. There are clinics and classics and occasional clunkers. This one is just...weird.2017-8-31 22:07:30
In the end, a win's a win. Federer now needs to string together five more of them to earn his sixth U.S. Open triumph and his third Grand Slam this season.
Rafael Nadal joined Federer in the winner's circle, although his path to a triumph was also a bit bumpy.
World No. 121 Taro Daniel gave Nadal all he could handle early on, and he secured a break at 5-4 in the first set that served as a springboard to a surprising early lead.
However, that was as good as things would get for Daniel.
Nadal was in cruise control from that point forward, and he secured a spot in the third round by dictating pace in vintage fashion over the final three sets.
With the minor scare behind him, Nadal will set his sights on a third-round date with Leonardo Mayer.
Upsets marked the rest of the men's draw on Thursday, as No. 7 seed Dimitrov and No. 15 seed Berdych both lost. Dimitrov became the four men's top-10 seed to either drop out of the tournament or lose, a disappointing development in New York.
Rublev told reporters after the match:
"I know that Grigor is a much more experienced player than me. Before the match I was thinking that I would have to play the match at my rhythm and my speed, because I know that at my speed I can play with anybody and compete with the top players. The main thing was to try to find my rhythm and play my game, and in the end I did that."
The women managed to avoid any enormous upsets, meanwhile, though No. 1 Pliskova needed all three sets to advance past Gibbs. While Pliskova was sluggish for much of the match, she ratcheted up her intensity late, winning 11 straight points in the final set, while Gibbs hit 13 unforced errors, per WTATennis.com.
No. 4 Svitolina moved on as well, winning in straight sets and showcasing her immense ability in the process.
US Open Tennis @usopen
.@ElinaSvitolina comes out strong in her first set vs Rodina. 6-4 #USOpen @MBUSA https://t.co/3wbkWUt1uW2017-8-31 16:37:51
With the women's draw wide-open, she remains a serious contender in New York.
Finally, Shelby Rogers won an absolute marathon of a match to move on.
US Open Tennis @usopen
.@Shelby_Rogers_ wins the longest recorded women's match in #USOpen history (3h, 31m) over Gavrilova 7-6, 4-6, 7-6! https://t.co/tc7zxWOO05 https://t.co/19MX5haWqN2017-8-31 21:09:29
US Open Tennis @usopen
3 hrs and 31 minutes on court... Get some well deserved rest, @Shelby_Rogers_! #USOpen https://t.co/ozLbG41p6H2017-8-31 21:29:14
A well-earned rest, indeed.