A mental reset helped world number one Iga Swiatek charge into the third round of the US Open on Thursday with a 6-0, 6-1 rout of 217th-ranked Ena Shibahara.

Swiatek had looked shaky at times in her first-round victory over lucky loser Kamilla Rakhimova, but the Polish star, aiming to add a second US Open title to her stash of four French Opens, dominated Japan’s Shibahara, who was in the main draw of a Grand Slam for the first time.

She needed just 65 minutes to advance to play either 25th seed Anastasia Pavlyuchenkova or Elisabetta Cocciaretto for a place in the last 16.

She won the first seven games before Shibahara held serve to make it 1-1 in the second set, holding her nerve to save three break points in a 13-minute game that would be the only game she won.

Swiatek said the turnaround wasn’t a matter of changing her game.

“I kind of have the tools, but sometimes it’s just hard to use them,” Swiatek said. “I couldn’t really focus well on my first-round match, and I wanted to improve that.

“I gave myself time and acceptance that it may not be perfect, but step by step I can have better focus and have better mindset. Today it was for sure a little bit better.”

Swiatek said she had used her off-day practice to “get my rhythm”.

“I felt like I can play in a much more solid way, and I was making for sure better decisions,” she said.

Swiatek has won five titles this year to take her career total to 22. In addition to another French Open triumph she won at Rome and Madrid and on the hard courts of Indian Wells and Doha.

Despite her sustained success in recent years, the 23-year-old said sky-high expectations can still sometimes affect her adversely on court.

“Usually I don’t feel well on court when I have too big expectations … because of that I make wrong decisions on court,” she said.

“So I just try to kind of reset and to remember that I don’t have to play perfect tennis all the time.”

bb/dj