Naomi Osaka has revealed she gets "quite frustrated" with the challenges of playing on clay and is finding it "mentally taxing".
The four-time Grand Slam champion is yet to reach a final on the surface and was beaten in the second round of the Madrid Open last week.
She is set to return to action at the Italian Open this week before heading to Roland-Garros, where she will try to progress past the third round for the first time.
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Reflecting on her approach on clay, she said: "I’m not sure if I should be telling you this, but I’m just not that comfortable on it still, and I’m not sure if it’s because I need to play longer on it or if I just haven’t grown up on it.
"At the beginning when I first started training on clay, physically it was definitely very hard, but I’m the type that adapts quite quickly physically. So, I would just say mentally it’s a bit harder because you have to structure the points differently.
"I also think there are bad bounces and stuff. I get quite frustrated. So, yeah, mentally I think it’s a bit more taxing.
"But I think as soon as I get that sort of block out of my mind, then I’ll be more open to the mistakes. Right now, I’m taking everything as a learning process, and I’m trying not to be so hard on myself."
Osaka, who has played just two matches on clay since the 2019 French Open, is in the same half of the Italian Open draw as Serena Williams, who hasn’t played since the Australian Open in February.
Osaka says she has mixed feelings about delaying this year's French Open by a week, but hopes it will give her the opportunity to improve further on clay.
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"In the beginning I was a bit sad because it means more time away from home. But at the same time I feel like I need the extra time on clay, especially with my past results. Hopefully I do better here.
"But I’m not really mad at, I guess, grinding on clay and practising here for a couple more weeks."
Osaka also isn't too annoyed that she isn't winning as much on clay as she is using every match as a learning experience.
"I feel like that's the reason why I'm here, for match prep. I think actually in a weird way I'm kind of glad I'm not winning. I know that sounds a bit off, but I feel like I'm learning a lot.
"It kind of gives me a lot of drive to practice harder and to learn from all my practices.I don't take it in a bad way that I haven't played a lot of matches."
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