Top seed Novak Djokovic survived a first-set wobble to reach the US Open third round Friday but Wimbledon runner-up Sabine Lisicki once again flopped when removed from her London grasscourt comfort zone.
World number one Djokovic won 12 of the last 14 games to defeat Germany's Benjamin Becker 7-6 (7/2), 6-2, 6-2 after saving two set points in the 10th game of the opening set.
Djokovic, the 2011 champion who is bidding to reach the New York final for a fourth successive year, sent down 13 aces as well as 40 winners with 18 of his 26 total unforced errors coming in that uncomfortable first set against the world number 87, who is part of US Open folklore.
It was the 32-year-old German who ended Andre Agassi's career in the American's last match in New York in 2006.
"Becker is a quality player and he should have won the first set. I was fortunate to come out of it, but after that I felt more comfortable on the court," said Djokovic, who next plays either Jarkko Nieminen of Finland or Portugal's Joao Sousa.
In the women's event, Chinese fifth seed Li Na and third-seeded Pole Agnieszka Radwanska made the last 16.
Li hit 11 aces in a 6-2, 7-5 victory against teenager Laura Robson, avenging her loss to the Briton at the same stage last year.
The 31-year-old Li, who saw her opponent hit 30 unforced errors, goes on to face either Japanese qualifier Kurumi Nara or Serbian ninth seed Jelena Jankovic, the 2008 runner-up, for a quarter-final spot.
"I was really happy how I was hitting on the court," Li said. "And I thought I served really well."
Li's best US Open performance was a run to the quarter-finals in 2009, one round better than Radwanska, who has stumbled at the fourth-round stage on three occasions.
The 2012 Wimbledon runner-up made the last 16 once again on Friday with a 6-4, 7-6 (7/1) win over Russian 32nd seed Anastasia Pavlyuchenkova, a quarter-finalist in 2011.
Pavlyuchenkova, seeded at a major for the first time, was undone by 41 unforced errors, which rendered her 32 winners irrelevant against the steady Radwanska who now faces Ekaterina Makarova.
Russian 24th seed Makarova clinched a 6-4, 7-5 win over German 16th seed Lisicki, who had wowed Wimbledon last month when she defeated Serena Williams on her way to a final loss against Marion Bartoli.
That took her record to 19-5 on the grass of the All England Club but she now stands at a mediocre 18-16 at the three other Slams, where she has never gotten beyond the fourth round.
Makarova, a 25-year-old left-hander who was a quarter-finalist at the Australian Open this year, now has eight career wins over a top-16 seed at a Slam.
Later Friday, defending champions Andy Murray and Serena Williams will take centre stage.
Murray, who had to wait until Wednesday night to get his title defense underway, tackles Leonardo Mayer, the Argentine world number 81, for a place in the last 32.
The third-seeded Scot has played in the finals of the last four Grand Slam tournaments in which he has competed, a run which included a first Wimbledon title last month.
Four-time champion Williams, the top seed, has dropped just four games in her opening two matches and takes on big-hitting Russian-born Kazkhastan player Yaroslava Shvedova, the world number 78, for a last-16 spot.
Williams, chasing a 17th Grand Slam title, has won both their previous meetings, at Toronto in 2009 and Wimbledon last year.
Shvedova has twice been a women's doubles champion at the US Open, partnering Vania King to victory in 2010 and 2011.
Friday's action also sees two former men's champions clash for a place in the third round when Australia's 2001 winner Lleyton Hewitt meets Argentina's Juan Martin Del Potro, the sixth seed who claimed the 2009 title.
In other early men's action Friday, 12th seeded Tommy Haas, the oldest man in the draw at 35 and a three-time quarter-finalist, defeated Lu Yen-Hsun of Taiwan 6-3, 6-4, 7-6 (7/3).
The 35-year-old German next plays Russian 21st seed Mikhail Youzhny, the two-time semi-finalist, who saw off Alexandr Dolgopolov of Ukraine 7-5, 6-1, 6-3, for a fourth-round place.