Naomi Osaka overcame intense nerves and a stuttering start to open her US Open title defence with a 6-4 6-7 (5) 6-2 win over Russia’s Anna Blinkova and reach the second round in New York.

The world No 1 returned to the scene of her first grand slam title preoccupied by a knee injury after she was forced to retire from her quarter-final match in Cincinnati. After limping off the court on 16 August she was resolute: “In the end, I’m going to play even if the doctor says no.”

The 21 year-old played with a support on her left knee but her movement looked comfortable throughout. It was her ground strokes that were the problem as she struggled to find consistency.

“I don’t think I’ve ever been this nervous in my life,” Osaka said. “She played really amazing and for me I just came off really slow. For me, I don’t think I found my rhythm but I fought as hard as I could.”

Osaka reeled off five successive games to take the first set 6-4 but after grabbing hold of the match the world No 1 lost the tie-break in the second. Early in the final set, Osaka was forced to save three break points.

“There were moments where I played really well, and then moments where I didn’t play as well,” she said. “I think as a whole, I just need to learn how to stay more consistent on the good side.”

The two-time grand slam champion’s victory at the Australian Open in January completed her ascension to the number one ranking, but much of her year has seen her learn to deal with the attention and pressure of being the best. Against Blinkova, she resolved to stand up to the pressure.

“I remember two years ago I played Kerber here,” said Osaka. “She was the defending champion. And I could see how stressed out she was when I was playing her. I don’t want to give people that look.“

Elsewhere, Wimbledon champion Simona Halep scuppered lucky loser Nicole Gibbs, while 19 year-old Canadian sensation Bianca Andreescu, who captured the Rogers Cup title at home in Toronto earlier this month, eased past 17 year-old Katie Volynets 6-2 6-4.

Sixth seed Petra Kvitova, who has been troubled by a forearm injury since withdrawing from the French Open, moved on with a 6-2 6-4 win against qualifier Denisa Allertova.