Poland's third seed Agnieszka Radwanska has been bundled out of the US Open by Russia's Ekaterina Makarova in the biggest shock of the women's event at Flushing Meadows.
Croatian Borna Coric saved six match points as he rallied from 5-1 down in the fourth set to stun Stefanos Tsitsipas 6-7(2), 6-4, 4-6, 7-5, 7-6(4) and send the fourth seed tumbling out of the US Open in the third round on Friday.
IMAGES from matches on Day 4 of the US Open at Flushing Meadows in New York on Thursday.
Tommy Robredo suspected he could stun Roger Federer at the US Open because the Swiss master had developed self-doubts, the Spaniard said after the extraordinary upset on Monday.
The fifth seeds advanced to the final of the men's doubles at the US Open on Thursday after their Spanish opponents Marcel Granollers and Marc Lopez had to retire because of injury.
Russians Nadia Petrova and Maria Kirilenko avenged a pair of stinging London defeats by beating Venus and Serena Williams in the women's doubles at the US Open on Monday.
Former champion Marat Safin's grand slam career came to an end when he punched a backhand into the net to end a two-hour, 13-minute match, going down to Austrian Juergen Melzer in the first-round on Wednesday.
Tenth seed Flavia Pennetta dished out the first whitewash of the US Open on Wednesday when she demolished India's Sania Mirza 6-0, 6-0 in the second round.
A summary of Friday's action at the US Open.
Federer, Djokovic headline Day 2 at Flushing Meadows
World number one Dinara Safina was beaten 6-4, 2-6, 7-6 in the third round of the US Open on Saturday by little-known Czech Petra Kvitova.
Third seed Novak Djokovic survived an epic five-set encounter against Czech Radek Stepanek, fighting off exhaustion and crippling cramps to reach the third round of the US Open Friday.
Serena Williams was the runner-up in Flushing Meadows each of the past two years
Giovanni Bartocci stood outside Billie Jean King National Tennis Center on Saturday shouting encouragement - and eventually employing a microphone and loudspeaker - as the Italian dismantled opponent Casper Ruud in straight sets on Court 17.
Sixteen-year-old Coco Gauff said her game is the "best it's ever been," as she aims to build on her Grand Slam success as the US Open kicks off on Monday.
The tournament initiative was to launch on Wednesday - Ukraine Independence Day - with the exhibition event at Louis Armstrong Stadium
American Todd Martin announced his retirement after losing to Fabrice Santoro of France in the first round of the U.S. Open on Monday.
Amanda Anisimova has confessed that she was a bundle of nerves after staring down the barrel of an early exit from the US Open during her second-round battle against fellow American teenager Katrina Scott on Thursday.
Images from Day 6 of the 2021 US Open in New York on Saturday.
IMAGES from Day 8 of the action at the US Open at USTA Billie Jean King National Tennis Center at Flushing Meadows in New York on Monday.
Images from Day 5 of the 2021 US Open in New York on Friday.
A summary of Monday's action at the US Open.
Serena Williams returns to the Arthur Ashe Stadium on Sunday
India's Sania Mirza and her partner Cara Black of Zimbabwe could not make it to the US Open women's doubles finals after going down in straight sets to Swiss-Italian pair of Martina Hingis and Flavia Pennetta at the Flushing Meadows.
'Everyone always talks about how hot Melbourne is but the US Open's way worse'
Sania Mirza and Jie Zheng moved into the semi-finals of the women's doubles with a straight sets win over Su-Wei Hsieh and Shuai Peng.
Muchova, who came into the match against the 12th seed with a world ranking of 202, was understandably nervous from the outset but grew into the contest and eventually prevailed 3-6, 6-4, 6-4 in two hours and 27 minutes.
World number one Simona Halep was upset 6-2, 6-4 by unseeded Estonian Kaia Kanepi in the U.S. Open first round on Monday, the second consecutive year the Romanian has lost her opening match at Flushing Meadows.
Top-seeded world number ones Serena Williams and Novak Djokovic help launch the US Open tennis championships on Monday's opening day of the year's final Grand Slam.
Roger Federer won five consecutive US Open titles from 2004-2008 but has not enjoyed much success here recently.
'I think we should have a heat rule, it's not healthy to be out there getting dizzy and stuff and the poor ball kids out there. There should definitely be a heat rule looked at and put into place'
Steady rain hit the US Open on Monday, washing out the last match on Arthur Ashe Stadium court featuring five-time champion Roger Federer.
Images from Day 1 of the US Open in New York, on Monday.
After 17 trips to Flushing Meadows and six US Open titles Serena Williams did something on Thursday she had never done before -- win a match indoors.
'Everybody knows that they could wait a little bit, no? It was an unfortunate decision.'
Defending champion Naomi Osaka of Japan was upset 7-5, 6-4 by Belinda Bencic in the fourth round at the US Open on Monday as the Swiss reached the quarter-finals for the second time.
A summary of Sunday's action at the US Open.
Competing in his fourth straight Grand Slam singles main draw this season, Prajnesh lost 4-6, 1-6, 2-6 to the Russian on Monday.
Prajnesh Gunneswaran got a taste of high-level tennis in his first-round exit from the US Open, losing to world number five Daniil Medvedev in 84 minutes, in New York, on Monday.