Japan's Naomi Osaka reacts after beating Czech ace Katerina Siniakova on Wednesday.

After years of having a rather strained relationship with Wimbledon, thanks to being "paralyzed by fear" at the thought of playing on tennis' fastest surface, Naomi Osaka feels she has finally found her feet on grass.

The Japanese player, who has won all four of her Grand Slam titles on the hard courts of Melbourne Park and Flushing Meadows, has never found her comfort zone on the green, green grass of Wimbledon, making only four previous appearances during her 10-year professional career.

During those four visits to the All England Club, she won a total of just five matches, with third-round showings in 2017 and 2018 being her standout performances — hardly anything to shout about for a woman who has been ranked world No 1.

But, after matching her best ever Wimbledon showing on Wednesday with an impressive 6-3, 6-2 win over Czech Katerina Siniakova, who has won the Wimbledon women's doubles title three times, Osaka feels she has finally overcome the fear factor on grass.

"When I was younger, I had no fear. I think when you are young, you fear nothing, and that's one of the really cool things about it," explained Osaka, now ranked 53 as she continues to try to recapture her best form after taking a maternity break in 2023.

"But, with age, fear kind of crept along and, I guess, paralyzed me in a way. Now, I'm kind of just getting over that and trying to spread my wings on grass.

"I think it is working, and I think I am moving pretty well. Yeah, I just hope that, in years to come, and hopefully this year, I can do a lot better in this tournament."

Osaka could not have picked a better year to enjoy a deep run at Wimbledon.

Following the harvesting of seeds that has taken place in the first three days, the highest ranked players she could meet before a potential semifinal against either world No 1 Aryna Sabalenka or Australian Open champion Madison Keys are No 13 Amanda Anisimova or No 30 Linda Noskova — neither of whom are known for their grass-court pedigree.

After two straight-set victories, she will certainly fancy her chances of defeating Anastasia Pavlyuchenkova to reach the last 16 for the first time in London, considering the Russian has not beaten her since 2017.

"Definitely, this year, I feel a lot more comfortable moving on grass," said Osaka after improving her Wimbledon win-loss record to 7-4 on the day her daughter Shai celebrated her second birthday.

"I know the last couple of years I was really scared to move, because when I was younger, I strained my knee, or whatever. It took a couple of years to get over that, but I definitely feel a lot more comfortable."