Top-seeded Novak Djokovic moved into third round of the US Open with a 6-1, 6-3, 6-0 rout of Frenchman Paul-Henri Mathieu on Thursday.
Djokovic, who danced for the fans, doing a sort of salsa to Iggy Azalea's summer hit "Fancy," after his victory, next faces American Sam Querrey, who downed 28th-seeded Spaniard Guillermo Garcia-Lopez in straight sets.
In other action under the lights, 2012 US Open champion Andy Murray moved easily into the third round with a 6-3, 6-3, 6-4 victory over Matthias Bachinger.
The eighth-seeded Murray, who battled cramps in his hamstring, shoulder and arm during a four-set win over Robin Haase in the heat of the day Monday, showed no such trouble on a crisp, 75-degree night in Arthur Ashe Stadium.
Murray has not reached a final since winning Wimbledon in 2013. He next faces Andrey Kuznetsov of Russia.
No. 13 John Isner advanced to another third-round matchup with 22nd-seeded German Philipp Kohlschreiber, the man who has beaten him the same round the past two years.
Isner, the highest-ranked American man, hit 30 aces and saved the only break point he faced in a 7-6 (5), 6-4, 6-2 victory over 77th-ranked Jan-Lennard Struff of Germany.
In a real -- and, as Isner put it, "bizarre" -- example of the luck of the draw, he now will face Kohlschreiber, who advanced when his opponent, Michael Llodra, stopped because of an injured left elbow.
It will be the third year in a row Isner plays the exact same guy in the exact same round at the US Open. Kohlschreiber eliminated Isner in five sets in 2012, and in four sets in '13.
As Isner pointed out Thursday, he has won the pair's four career meetings at other sites.
This annual reunion is not unprecedented.
According to the ATP, there are other examples of men playing each other over and over in the same round at the same event.
One example: Roger Federer met Novak Djokovic in the US Open semifinals four consecutive times from 2008 to '11.
Others through easily included No. 9 Jo-Wilfried Tsonga and No. 10 Kei Nishikori.
Nishikori was leading 6-4, 6-1 when 48th-ranked Pablo Andujar suddenly came to the net. Tournament officials did not immediately detail the nature of the Spaniard's injury.
"It's unfortunate for Pablo today, but I have been playing well ... had good two sets," said Nishikori, who has never made it past the fourth round in five previous US Open appearances.
Among the noteworthy results Thursday was the 7-6 (2), 4-6, 6-4, 6-2 win by Victor Estrella Burgos of the Dominican Republic against Borna Coric of Croatia. Playing in the US Open for the first time at age 34, Estrella Burgos eliminated a player half his age in the 17-year-old Coric, making for the largest gap between male opponents in US Open history.
And their ages weren't the only discrepancy Thursday: The 5-foot-8 Estrella Burgos had to stretch his arms when he reached up to console the 6-foot-1 Coric at the net after winning 7-6 (2), 4-6, 6-4, 6-2 to get to the third round at Flushing Meadows.
"Age is just a number," said the 80th-ranked Estrella Burgos, the first player from the Dominican Republic to reach the ATP's top 100. "For me, it never is a factor. I knew about his age, and that I was playing someone who has a bright future ahead of him, but I never thought that I have to beat him because he was younger than me or that he will just fail by just being younger."
The Associated Press contributed to this report.