France, Feb. 16 -- Serena Williams moved into the semi-finals of the Australian Open on Tuesday following a 6-3, 6-3 win over the second seed Simona Halep.

Williams, 39, will play third seed Naomi Osaka on Thursday after the Japanese 23-year-old dismissed Taiwan's Hsieh Su-wei 6-2, 6-2.

Osaka hit 24 winners as she swept past the 35-year-old who was playing in her first Grand Slam quarter-final.

"I told myself just to be really intense from the beginning," said Osaka. "I felt like I knew what to expect and that I couldn't afford to be lazy with my footwork or anything."

After her victory over Halep, Williams said she had also been on her game.

"Definitely think this is the best match I have played this tournament, for sure," said the ...