INDIAN WELLS, CA, USA - 20-year-old Naomi Osaka is through to the BNP Paribas Open semifinals for the first time in her career after stunning No.5 seed Karolina Pliskova in straight sets.

Osaka’s methodical, 6-2, 6-3 victory earns her the first Top 5 win of the year - as well as a matchup against World No.1 Simona Halep in the next round.

"I have played her before, so I already knew what to expect," Osaka told reporters afterwards.

"I would say I made a lot of unforced errors while not really going for the shots that I had. So I'm just trying to commit more and also playing longer rallies at the same time.

"So, yes, that, and also just being happy to be in this position right now."

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Osaka took advantage of a sluggish, error-strewn start from Pliskova to take an early break lead - Pliskova surrendered the game with a double fault, her first of six in the match. The Japanese player enjoyed the rhythm of Pliskova’s game, using the pace from Pliskova’s booming, flat strokes and returning them all with interest, building up a quick 4-1 lead.

Pliskova only had one chance to break the rock-solid Osaka - who won 92% of points behind her first serve - in the opening set, but the Japanese player brushed it aside with a perfectly placed backhand down the line.

Osaka didn’t allow Pliskova to impose her game, keeping her under pressure throughout and forcing her to go for bigger shots - drawing out the unforced errors. outsteadying Pliskova to grab the opening set.

A marathon eight-minute game gave Osaka the opening break in set two, carrying on her momentum without a hitch. But instead of letting it get away from her Pliskova grabbed the break straight back, solving the Osaka serve for the first time in the match.

But the parity was short-lived as once again the Japanese player emerged with the lead after a spate of four straight breaks. Osaka raised her level to reel off the last four games in a row to put a commanding end to the match after an hour and 20 minutes.

“I think I guess everything was a little bit off from my side, for sure, today,” Pliskova admitted afterwards. “She was playing very well, hitting her spots - forehands, even the backhands.

“I just battling all the way, even in serving, returning. I was definitely not feeling the best. A little bit tired I felt maybe because of the waiting [for the previous match on court to finish]. I don't know.”

After taking out former World No.1 Pliskova in the quarterfinals, Osaka will face current No.1 Halep in the next round as she seeks the biggest win of her career. Osaka trails Halep 0-3 in their head-to-head record, with the Romanian knocking out Osaka in the Australian Open round of 16 earlier this year.

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