World No 2 Djokovic, who received a first-round bye, broke his opponent's serve four times to extend his winning run to 19 matches.
World number one Simona Halep pulled out of next week's WTA Finals due to a lower back injury.
Defending US Open champion Rafael Nadal and twice winner Novak Djokovic are one victory away from renewing their rivalry in the final with both expected to get through their semis on Friday.
Pruthviraj Kandepi, who hailed from Guntur district of Andhra Pradesh, was killed in the shootout.
Serena Williams returns to the Arthur Ashe Stadium on Sunday
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.
The Scotsman doesn't expect to win US Open this year
This time last year, Federer was the pundits' pick to claim a third Grand Slam title of 2017 in New York, after roaring back from a season decimated by injury to win the Australian Open and Wimbledon.
An elbow injury forced Djokovic to retire against Czech Tomas Berdych in the quarter-finals of Wimbledon in 2017. After that came a series of early tournament exits and, finally, surgery.
Frenchman Jo-Wilfried Tsonga has withdrawn from the US Open due to a long-term knee problem, the United States Tennis Association said on Monday.
Four times now, twice at Wimbledon (2018, 2019) and at the US Open (2018, 2019) Serena Williams has come agonizingly close to that 24th Grand Slam only to fall at the final hurdle.
Novak Djokovic finally clinched the title missing from his resume with a 6-4, 6-4 win over Roger Federer on Sunday to win in Cincinnati and become the first player to complete the sweep of Masters series tournaments on Sunday.
Zeeshan Ali, the captain and coach of the men's team, has no clue about Paes's arrival three days before the start of the competition on Sunday.
Former World No 1 Azarenka, the winner of two Australian Open titles and twice a US Open runner-up, withdrew from last year's tournament at Flushing Meadows because of a child custody battle.
World No 1 Novak Djokovic needed three sets to get past Gilles Simon in the Western and Southern Open second round on Tuesday, but Jo-Wilfried Tsonga lost to Mikhail Youzhny in his opener two days after winning the Rogers Cup in Toronto.
Top seed Rafa Nadal overwhelmed Russia's Daniil Medvedev 6-3, 6-0 to win his fifth Rogers Cup on Sunday in Montreal -- the first time he has retained a title outside of clay.
This would be for the second time that Thapar, son of Indian-American immigrants, might not be able to make the final cut after being interviewed by the US president.
Summary of sports events and persons who made news on Monday
'I had to learn to be patient. I am a different player and a different person than I was three years ago. I still believe I can repeat that 2015-2016 streak when I won four slams in a row, I wouldn't be here if I didn't.'
In the absence of an injured Yuki, a lot would depend on how the left-handed Prajnesh, who won a singles bronze medal at the Asian Games, performs.
Since his June trek with his wife up Mont Sainte-Victoire, the mountain that famously also served as an inspiration for Paul Cezanne, the 31-year-old has added a pair of Grand Slam titles to his resume.
Although Kyrgios dropped the opening set his level of play and interest rose dramatically after the pep talk and he swept the next three sets for a 4-6, 7-6(6), 6-3, 6-0 win.
Sloane Stephens will be defending her title at the U.S. Open but all eyes will be on Serena Williams over the coming two weeks as the six-times champion attempts to win her first Grand Slam title since becoming a mother.
Fourth seed Agnieszka Radwanska of Poland withdrew from the Western and Southern Open for personal reasons on Thursday, sending defending champion Li Na of China through to the semi-finals.
Dimitrov has enjoyed the best season of his career in 2017, clinching four titles overall, including his first Masters title in Cincinnati.
The 26-year-old has not always handled the expectations placed on his shoulders after he won the Wimbledon junior title in 2008 with a game style uncannily like Federer's.
Simona Halep believes this year's French Open victory has helped justify her position as the women's world number one
In the last eight weeks Novak Djokovic has resembled the Grand Slam machine that held all four major titles at the same time in 2016, wining three of his last four events including Wimbledon and US Open.
India's Sania Mirza and her women's doubles partner Barbara Strycova crashed out of the BNP Paribas Open after going down in straight sets in the quarter-finals at Indian Wells.
Here is a player profile, a look at the form and records of American Madison Keys and compatriot Sloane Stephens ahead of Saturday's US Open final (prefix number denotes seeding)
Venus Williams will take on compatriot Sloane Stephens in one semi-final before her fellow Americans Madison Keys battles it out with CoCo Vandeweghe in the other in all-American semi-final in the women's singles at the US Open.
Federer looked more relieved than overjoyed when Tiafoe's forehand found the net on match point to keep his hopes of a 20th grand slam title alive.
'It was exciting and this is why I came to New York, to go through these emotions'
While the year's final grand slam is just underway tennis fans have circled Sept. 8 when, if all goes to form, Nadal and Federer would meet to decide a place in the final.
Now with Serena sidelined for the impending birth of her first child, the two-time grand slam winner is delivering on the promise that could see her become the new face of women's tennis.
Milos Raonic has withdrawn from the US Open due to a persistent wrist injury but plans to return to the Tour later in the year, the Canadian said on late on Wednesday.
American great John McEnroe expects Roger Federer's sensational comeback season to continue in New York when the US Open kicks off on Monday.
Rafael Nadal announced on Sunday that he would be opening his 18th season as a professional at the Brisbane International in January.
While Venus has been doing pretty well on-court, the 37-year-old is busy with some off-court chores and it reads - online shopping for the newborn.
Former world number one Maria Sharapova will make her first Grand Slam appearance in over 18 months after she was awarded a main-draw wildcard for the upcoming US Open, the tennis tournament's organisers confirmed on Tuesday.