NEW YORK — Coco Gauff had an easy start to her US Open title defense, rolling to a 6-2, 6-0 victory over Varvara Gracheva on Monday.

Gauff needed just over an hour, looking more like the player who won her first major title last year at age 19 than the one who had dropped her last two matches before coming to New York. But Gauff said that she had practiced well since those losses in Toronto and Cincinnati and that she wasn’t surprised it showed in her play.

“So honestly, I was just telling myself that I’m ready,” Gauff said.

“I feel like I’m finding my game, whereas the other two tournaments that I played at, even the practice sessions I was doing, I just felt off.”

Zheng Qinwen, the Olympic gold medalist in women’s tennis, stayed in the tournament by rallying for a 4-6, 6-4, 6-2 victory over Amanda Anisimova.

Zheng began the Grand Slam season by reaching the final of the Australian Open. She had a difficult assignment to start the year’s final major in Anisimova, an American who earlier this month reached the final of a hard-court warmup tournament in Montreal and returned to the top 50 of the WTA rankings.

But the No. 7 seed from China solved Anisimova’s power as the match went on to move into the second round as she turns her attention back to the Grand Slams after becoming China’s first singles gold medalist at the Paris Olympics.

“You have the first one, of course you’re going to stay a long time in the successful feeling. I did that in the Australian Open but I was just in the final, and the effect takes me so long to come back to reality,” Zheng said.

“I had this experience already, so this time when I had success in the Olympic Games, to come to the next tournament, I say, everything starts at zero. You are not anymore the Olympic champion. Just be humble and try to work, fight every single match, because if you don’t fight, you have a big chance to lose.”

Maria Sakkari, the No. 9 seed from Greece, became the first seeded player to be eliminated when she stopped playing after losing the first set against China’s Wang Yafan. Sakkari, who also lost in the first round last year at Flushing Meadows, received treatment on her shoulder in the first set.

Men’s winners Monday included No. 4 Alexander Zverev, No. 6 Andrey Rublev, No. 8 Casper Ruud, and Americans Taylor Fritz and Ben Shelton, the Nos. 12 and 13 seeds. Shelton eliminated 2020 US Open champion Dominic Thiem, who was playing his final Grand Slam match before retiring after wrist injuries.

Defending champion Novak Djokovic plays Radu Albot in the last match in the main stadium Monday night.

The No. 1 women’s and men’s singles seeds, Iga Swiatek and Jannik Sinner, are slated to play their first-round matches Tuesday.

Sinner has been the center of attention since news emerged last week that he tested positive for steroids twice in March but avoided a suspension.