Madrid - After a week of training on the clay courts of the Rafa Nadal Academy in Mallorca, Naomi Osaka feels she's rediscovered the form that had been missing since her Australian Open triumph in January.
The top seed at the Madrid Open this week, Osaka says she's ready to return to action and isn't too concerned about the abdominal injury she sustained in Stuttgart where she reached the semi-final last week.
The world No 1 was forced to withdraw ahead of her semi-final against Anett Kontaveit at the German tournament but was seen hitting at Madrid's Caja Magica on Friday, and says she's pain-free.
"I haven't served up until today and basically I was just resting it," Osaka told reporters in the Spanish capital on Friday.
"Of course I hit ground strokes for the past three days because it's not like I could fully rest, but it's not painful, so I think it's looking good."
Seeking her first title on clay, Osaka opens against 2016 runner-up Dominika Cibulkova in Madrid.
Following a second consecutive Grand Slam triumph at the Australian Open in January, the 21-year-old Osaka lost some momentum.
The Japanese-Haitian star parted ways with her coach Sascha Bajin and suffered an opening round defeat in Dubai, a fourth-round exit in Indian Wells - where she was the defending champion - and a third-round loss in Miami.
She hired Jermaine Jenkins as her coach ahead of Indian Wells, and says she feels like Stuttgart has got her back on track.
"I think in Stuttgart, I did pretty well," she said.
"I played two really hard matches and I think that I just was able to turn a switch on that I haven’t been able to since the Australian (Open).
"It was really fun actually, those matches, so I'm really looking forward to my next one," added Osaka.
All three of Osaka's career titles so far have come on hard-courts but she believes she's been successfully adjusting her mentality on clay in order to contend at Roland Garros.
"I think it's fitness and also mental. Because last year I thought the number one thing I could have improved on, on clay, is just prolonging the point, or like accepting when I have to back off being aggressive," she said.
"So then when I played Donna (Vekic in Stuttgart) ... I just remember telling myself that I don’t have to hit a winner for it to be a good point and I don't have to play perfectly to win, so I think I was able to do that.
"I was a bit sad I couldn't continue that way of thinking because I had to withdraw but hopefully I can keep it here."
Osaka said she was impressed by Nadal's academy during her training block there, despite her shyness in meeting the Spanish 17-time Grand Slam champion.
"He’s a really nice person, he was sort of the one talking more than me, which you can kind of tell that that would happen," she said.
"Yesterday (in Madrid) he went on the court after me and he was talking to me again and I was like 'woah',” she said with a smile.
Defending Madrid champion Petra Kvitova, a losing finalist to Osaka at the Australian Open, is the number two seed at the Caja Magica and opens her campaign against talented 20-year-old Sofia "Sonya" Kenin.