Serena Williams won 10 games in a row to defeat countrywoman Vania King and reach the third round of the US Open.
The world number one, who is bidding to win a third straight title at Flushing Meadows, needed just 56 minutes to triumph 6-1 6-0.
Williams dropped only five points on serve in her first-round win over another American, Taylor Townsend, but struggled a little for rhythm on it in breezy conditions on Thursday.
However, she still did enough to not be broken and found King’s serve much to her liking.
The 25-year-old managed to hold in the third game but that was as good as it got as Williams turned on the power when she needed it.
After disappointing performances in all the grand slams so far this season, the world number one has been focusing on not over-thinking matters here.
And she has been noticeably calmer in her two matches so far.
King had her chances in the second set but Williams shut the door every time, more than balancing out the errors with winners.
When King netted the final backhand on Williams’ second match point, she was surely glad that the punishment was over.
Williams, who was wearing a shocking pink leopard-print dress, said: “It’s so hard to play in the wind. I’m really happy to get through a solid match with the conditions today.”
The 32-year-old next meets Varvara Lepchenko, her third successive American opponent.
Ana Ivanovic became the second top-10 player to crash out as she fell to Czech Karolina Pliskova.
After fourth seed Agnieszka Radwanska went down early on Wednesday, it was Ivanovic’s turn to suffer the early shock.
The eighth seed went into the tournament with high hopes of marking her best season since she won the French Open in 2008 with a good run in New York.
But she found world number 42 Pliskova in fine form and succumbed to a 7-5 6-4 defeat, with the 22-year-old reaching the third round at a grand slam for the first time in her career.
For all her success this year, winning three titles, deep runs at slams have continued to elude Ivanovic.
The honourable exception was the Australian Open, where she defeated Serena Williams to reach the quarter-finals, but she then went on to lose in the third round at both the French Open and Wimbledon.
Victoria Azarenka looked much sharper than in her first-round match, winning 12 of the last 14 games in a 6-3 6-2 victory over America’s Christina McHale.
Azarenka, the beaten finalist at Flushing Meadows the last two years, has had a nightmare season with injury and is seeded only 16th this time.
She needed three sets to battle past Misaki Doi in round one and lost the first three games to McHale before recovering in impressive fashion.
Eleventh seed Flavia Pennetta, a semi-finalist last year, made smooth progress with a 6-4 6-3 victory over America’s Shelby Rogers.