Naomi Osaka was expecting the question. Then again, it came hardly as a surprise. On Sunday, the bright new face of tennis made her first public appearance since <a href="http://www.thenational.ae/sport/tennis/dubai-duty-free-tennis-championships-to-be-naomi-osaka-s-first-tournament-without-sascha-bajin-as-coach-1.824673">the shock announcement she had split from coach Sascha Bajin</a>. The news arrived last week, via a relatively frank tweet on her official account. It came less than three weeks after Osaka clinched the Australian Open, not only a second grand slam title of her still-fledgling career, but a second successive major crown at that. It propelled the Japanese star, at age 21, to world No 1. Nevertheless, her professional relationship with Bajin was terminated. The link-up had stretched back more than a year, a year in which Osaka vaulted from outside the world’s top 70 to become the first Asian – male or female – to perch at the game’s summit. Between pre-Bajin and post-Bajin, she had won a first tournament, at Indian Wells, <a href="http://www.thenational.ae/sport/tennis/naomi-osaka-wins-us-open-after-serena-williams-umpire-thief-meltdown-1.768227">defeated Williams in the hugely controversial US Open final</a>, and outlasted Petra Kvitova in <a href="http://www.thenational.ae/sport/tennis/naomi-osaka-hungry-for-more-titles-as-world-no-1-targets-naomi-slam-1.818438">last month's epic battle for the Australian Open</a>. Osaka’s rise was not only memorable; it was meteoric. So, then, why the split? “Yeah, I was expecting this question," Osaka told the gathered media at Jumeirah Creekside Hotel, as she prepares for this week’s Dubai Duty Free Tennis Championships. "The main thing I know that everyone thinks it was a money-related issue, but it wasn’t. “For me, that’s one of the most hurtful things I’ve ever heard. Because I travel with everyone on my team, I see them more than my family, so I would never do that to them. “I think my reason is I wouldn’t put success over my happiness. That’s my main thing. I’m not going to say anything bad about him because I’m really grateful for all the things that he’s done. “I wouldn’t just come here and say anything bad. If anything, you would have to be around him to see, or ask him.” Asked when she made the call to call time on Bajin, Serena Williams' former hitting partner, Osaka replied: “It was kind of brewing in Australia and I think some people could see that if they saw how we interacted. “I wouldn't want to split on really bad terms, because he was sort of the one who made me open up to people, so I didn’t want it to be a really hostile thing.” Still, Osaka has a tight group around her this week. She joked that dad, Leonard Francois, will not be too conspicuous given he will be catching up on sleep, but she did confirm the search for Bajin’s replacement will begin in earnest once she is done in Dubai. “It's not really ideal to go to Indian Wells without a coach,” said Osaka, who appears to have already come to terms with what constituted a major decision. “I felt really happy. I'm surrounded by people that genuinely care. They have such positive energy. I'm really grateful for everyone that's around me at this time.” Despite that, not having Bajin in her corner this week would take some adjustment. The question of how prompted the WTA moderator to interject and request that line of questioning to cease, although, having fallen silent for a moment, Osaka responded: “It's OK. I'm just trying to figure out what I should say. “Of course, he does a lot of things and I'm going to miss some of those that he does. But for me, all the people that I have right now, they're all willing to do the things that he does. I don't think it will be that much of a big deal.” Given the past 12 months, Osaka is a pretty big deal herself. She will hope to deliver on that burgeoning reputation at the Dubai Duty Free Tennis Stadium, where she opens her third appearance in the Emirates – she reached the quarter-finals last year – on Tuesday with a second-round match against Frenchwoman Kristina Mladenovic. In many ways, the week represents fresh territory for Osaka, and not simply because Bajin is a notable absentee. It is her first tournament, too, since topping the rankings. Seeing that “No 1” next to her name has taken some getting used to. “Of course, I was really happy,” Osaka said. “But I feel like, I don't know... after the initial happiness, because it feels like a dream, and when you're little, you want to be No 1. “That's one of the things that comes out of your mouth whenever someone asks what your dream is. I had that moment of happiness, then I just wanted to practise more.” She should have enough time to do just that. After winning the US Open last September, Osaka traipsed the media circuit in America, which included an appearance on the Ellen DeGeneres show that, in turn, secured a message of support from Michael B Jordan. Osaka had earlier revealed the “Creed” actor as her celebrity crush. The fallout from the Australian Open, though, has been slightly more low-key. “People are bored of me now,” Osaka said, laughing. “They're over it.”