BIRMINGHAM, Great Britain - Naomi Osaka doesn't have any memories of playing on grass as "a little kid". That's because she never once stepped on the surface with her rackets, with the lawns as alien to her then as the far side of the moon. 

What Osaka does have, and they're playing in her head right now, are vivid recollections of being "crushed" underfoot on the Wimbledon grass, in a lopsided third-round match last summer against Angelique Kerber, the eventual champion. For all the splendour of Centre Court, it can be a brutal place to play tennis, with Osaka gathering just six games. 

Making the transition to the grass-court swing, other players might find themselves spooling back to a fine performance on the surface, but the World No.1 is using memories of her defeat to Kerber as a motivational tool.

If Osaka does well at the All England Club this year - having never gone beyond the third round on her previous visits - it will have something to do with Kerber. In Osaka's view, recalling that heavy defeat makes it easier to focus on what she needs to do to improve, and "the things that I have done wrong rather than the things I have done right". 

"Every match I play is a learning experience, of course. But it's funny, whenever I come to grass I can only remember the last match I played which is always Wimbledon and last year I played against Kerber and she kind of crushed me, so that is the thing that I remember the most," Osaka said ahead of her first-round match at the Nature Valley Classic in Birmingham, against Greece's Maria Sakkari.

"So I'm going to try and think about that match of course, but think about everything that I did, like sort of improved during the year." 

You might say that Osaka has been unfortunate at Wimbledon in the past, as she ran into Venus Williams in the third round of the 2017 tournament - with the American going on to make that year's final - and then Kerber at the same stage last summer.  

But Osaka - who has won the last two Grand Slams on hard courts, with titles at last year's US Open and this year's Australian Open - says herself that she doesn't feel at ease on grass. 

"You know, grass, I'm not really that comfortable with it. And it's always the first tournament that's the hardest. So, yeah, I have only practiced twice on grass because it was raining a lot. So, yeah, I guess I'm feeling as good as I can. It's just really different to everything I have played on. As a little kid, I never played on grass," said Osaka, though as a 21-year-old, she is now enjoying "the challenge and the fight" of playing lawn tennis. 

An early defeat at the clay-court French Open - where she lost in the third round to Czech Katerina Siniakova - allowed Osaka to have her first "mini-vacation" since winning the US Open last September. "I went home and I just sort of chilled for a week," Osaka said.

"Actually that week was the first time I took a complete week off and, honestly, I haven't felt like I rested ever. Like, I never took a vacation, so that was sort of my mini-vacation in a way. It was kind of refreshing because I felt like since the US Open things have been going so fast, so I felt like I really needed a break and it was good for me." 

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