Naomi Osaka's first match since splitting with her coach ended with a humiliating defeat

• Naomi Osaka just lost her first match since splitting with her coach Sascha Bajin.
• The 21-year-old, who had just won the 2019 Australian Open, was dumped out of the Dubai Tennis Championships in the very first round on Tuesday.
• Osaka was beaten in straight sets 6-3, 6-3 by the unseeded French player Kristina Mladenovic.
• Osaka made errors and failed to build any momentum in the match.
• Mladenovic now progresses to the next round on Wednesday, with a place in the quarter-final up for grabs. Osaka, meanwhile, has plenty of time to regroup and rethink her next move.

Naomi Osaka suffered a humiliating defeat in her first match since splitting from her coach Sascha Bajin.

Osaka's shock announcement that she had parted ways with Bajin stunned the tennis industry last week. The New York Times tennis journalist Ben Rothenberg even wrote that "the reasons for the split were unclear," adding that the news was "surprising."

Osaka and Bajin enjoyed a wildly successful ride in women's tennis, but ahead of the Dubai Tennis Championships this week Osaka said she left the trainer because she did not want to sacrifice her own happiness.

Her first round match against Kristina Mladenovic would be the first time Osaka played since parting with Bajin, and her first match since winning the 2019 Australian Open last month.

But, for Osaka, the Mladenovic match on center court at the Aviation Club Tennis Centre could not have gone much worse on Tuesday. She lost in straight sets 6-3, 6-3 against an athlete she was expected to beat.

It was a poor display from Osaka throughout, who failed to build any momentum winning only a maximum of five points in a row compared to Mladenovic's eight, and serving five double faults.

Mladenovic herself was a far more competent server with four aces and 56% first serve points won.

Watch the winning shot right here, which the commentator called "a very comfortable finish" for Mladenovic.

Osaka may have been a back-to-back Grand Slam champion and the newest number one in women's tennis, but Mladenovic kept her cool and secured her very first win over a woman ranked atop the world rankings.

For Osaka, dumped out of the Dubai tournament in the very first round, it's time to re-group and re-think before the Indian Wells Masters in California next month, while Mladenovic progresses to the next round in Dubai.

She plays Carla Suarez Navarro on Wednesday, with a quarter-final place at stake for the winner.

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