The 22-year-old Osaka fired 24 winners and committed 29 unforced errors, winning a narrow victory against her Belarussian opponent, whom she crushed 6-0, 6-0 at the US Open 11 months ago, after she lost in the first round last year at Cincinnati prior to winning her first major title at Flushing Meadows less than a month later, reports Xinhua news agency.
"It's the first match I have ever won here in the main draw, so I can't be too hard on myself, even though I naturally am," Osaka said. "I think that's something that I learn as I play more matches. Hopefully I'll have that opportunity."
This two-time Grand Slam champion will face Hsieh Su-Wei from Chinese Taipei in the next round, who beat Jennifer Brady 7-6 (9), 6-3 earlier in the day.
"I never know what to expect with her. But the last time I played her in Miami, I just remember being frustrated. So I think the time after that in Germany I was just trying to be focused, and I won that match. I'll just try to carry that on," she reflected.
In the Barty-Sharapova tie, the Australian fired 18 winners, breaking Sharapova four times as the Russian made 31 unforced errors in her 6-4, 6-1 defeat.
"I did a really good job, especially in winning some of the crucial games," the Australian said. "I love this time of year, getting back onto the hard courts and back to the summer here," she added.
The reigning sensation, 23, who scooped the French Open title this year, continued her devastating form to claim her 40th victory of 2019, denying her Russian opponent an opportunity to go further in the game.
It was the second time that Barty had beaten the five-time Grand Slammer who was once Cincinnati champion in 2011 after a win at the Australia Open.
Barty will face Estonia's Anett Kontaveit in the third round, who beat Polish teenager Iga Swiatek 6-4, 7-6 (2).
( With inputs from IANS )