On a rainy night in New York, Osaka defeated American Danielle Collins in straight sets – 7-6 (5) 6-3 – while defending champion Emma Raducano fell to Alizee Cornet.
Raducanu, 19, stunned the world by winning her first major at Flushing Meadows last year, but she has struggled to find a similar level since.
The veteran Cornet’s experience and intensity proved just too great as she was defeated in straight sets – 6-3, 6-3.
“Obviously it’s a little bit painful because it’s my favorite tournament and there’s been a lot of emotion last year,” she told reporters after the defeat.
“I’m proud to put myself out there in every game, every day, knowing I’m pushing myself to be the best that I can.”
Raducanu will fall into the rankings after a frustrating year plagued by injuries and changes to her coaching staff.
The young woman struggled to adjust to life on the full WTA tour, but showed flashes of quality that secured her first Grand Slam title just 12 months ago.
Cornet was simply in better shape and no longer a stranger to big results in four slams, having previously beaten players like Ega Swiatek at Wimbledon.
The Frenchwoman now holds the open-era record of appearing in the most consecutive four-slam tournaments, having appeared in the previous 63.
“I think I handle my feelings better,” Cornet told reporters after the match. “I think I’m getting older – more mature. It shows in my results. I’m 32 – better late than never.”
“You definitely yelled at me the last time.”
Osaka suffered a similar experience to Radokano but this time at the hands of talented Collins.
The world number 19 seed has never won a set against Osaka in all of his previous three encounters but has outpaced the Grand Slam champion this time around.
“When you lose to someone three times, you get a lot of information about what you can do better,” Collins told reporters.
“With Naomi being the player that she is, she yelled at me one last time. I just had to learn from that and make adjustments and I think I did.”
Osaka, a two-time US Open champion, was unseeded in this year’s event and is currently ranked 44th in the world.
She was struggling with momentum and form, she might have been an underdog coming into the first round but she put in a great performance despite the defeat.
Collins will now play Spain’s qualifying Cristina Bocoa in the next round while Cornet faces Katerina Siniakova.
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