Japan's 18-year-old Naomi Osaka reached the third round of her first Grand Slam on Thursday, defeating 18th seed Ukrainian Elina Svitolina 6-4, 6-4 at the Australian Open.

Born to a Haitian-American father and a Japanese mother, the 180-cm Osaka claimed four straight games from 3-1 down in the first set to take the initiative. She broke Svitolina's serve in the fifth game of the second set and was solid on serve, only losing two break points despite facing 11 in the straight-sets win.

"I was just thinking I have to be consistent and very steady and go for my shots when I have them," said Osaka.