'I was lonely': Naomi Osaka's heartwarming post about boyfriend

Naomi Osaka has sent a heartwarming message to her boyfriend during her Miami Open campaign where she is bidding to become World No.1.

Osaka returned to action for the first time since winning the Australian Open and defeated Aussie Ajla Tomljanovic in a hard-fought straight sets victory to advance to the Miami Open Third Round.

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But Osaka sent fans into a frenzy overnight after posting a heartwarming appreciation post about her boyfriend, American rapper Cordae, and his sacrifice during last year's US Open.

While Cordae wasn't able to travel with Osaka to Australia for this year's first grand slam, he did support her at last year's US Open.

And the World No.2 has revealed the sacrifice he made to join and support her during a difficult time.

"Appreciation post for the mister because I feel like it today," she wrote on Instagram.

"This pic was right after winning the US Open finals. He stopped everything he was doing because I FaceTimed him a couple days earlier and said I was feeling sad and lonely in the bubble.

"I later found out that he hopped on a plane shortly after that call and then quarantined himself for a couple days in a hotel to see me and support."

Osaka ended the post and joked she isn't sure Cordae understands the game.

"The funniest part is even after doing all this I’m still convinced he doesn’t understand the rules of tennis lol," she wrote.

Fans were taken aback at the heartwarming post.

Osaka continues winning streak in Miami

Tomljanovic, Australia's No.2 behind Ash Barty, again produced a performance which belied her world ranking of 77 as she gave Osaka plenty of problems in the opening set of their second round encounter on Friday.

But in oppressive, gusty conditions, Osaka's class - and huge serving - materialised at the crucial moments as she battled through to win a compelling tussle in one hour 41 minutes.

Ultimately, Tomljanovic's 24 unforced errors rather outstripped the good work she'd done with her 16 winners as she contemplated what might have been.

For Osaka, it meant a 22nd straight victory in all matches, her last defeat coming 13 months ago to Sara Sorribes Tormo in the Billie Jean King Cup.

Admitting afterwards that it had been hard work in her first contest since she won her grand slam in Melbourne against Jennifer Brady a month ago, Osaka noted on court that the difference had been that: "I was able to serve well when it really, really mattered."

with AAP

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