Wimbledon champion Iga Swiatek admitted she “made some mistakes” in a laboured three-set victory over world number 66 Suzan Lamens to reach the US Open third round.
Second seed Swiatek raced through the first set against her Dutch opponent and looked on course for the sort of dominant early-round win that has become her trademark.
The 24-year-old was twice a break of serve up in the second set, but her frustration grew as her level dipped significantly, giving Lamens a route back into the contest.
The Pole moved a double break clear in the decider and eventually wrapped up a 6-1 4-6 6-4 victory in two hours and six minutes on Arthur Ashe Stadium.
Swiatek will play 29th seed Anna Kalinskaya in round three after the Russian beat Yulia Putintseva of Kazakhstan 6-1 7-5.
Speaking on court after the match, Swiatek said: “It wasn’t an easy match and I made some mistakes. I’m happy that at the end I could be more proactive.
“I felt like it depended on me and whether I was going to make mistakes or not.
“It was not easy, but the third set is a reset. You’ve got to start from the beginning and I knew I could play a little more precisely, so I just tried to do that.”
All the signs before the match pointed to a comfortable Swiatek win.
She had lost only five games in her previous three Grand Slam matches – including a 6-0 6-0 victory over Amanda Anisimova in July’s Wimbledon final – and had won 14 successive sets at the majors.
US Open debutant Lamens, meanwhile, had not been beyond the second round of a Grand Slam before.
That gulf was evident early on, with Lamens failing to hit a single winner in the opening set.
But Swiatek, who won the Cincinnati Open in the build-up to Flushing Meadows, lost her way in set two.
The six-time Grand Slam champion and her coaching team began to show the frustration of some wayward groundstrokes, which contributed to a match total of 29 unforced errors.
Swiatek, though, regained some control in the decider and shrugged off handing back one of her breaks of serve to set up a tie with Kalinskaya.
