Osaka marches on in Tokyo

World number seven Naomi Osaka advanced to the semi-finals of the Pan Pacific Open following a powerful display on Friday.

The US Open champion was too good for Barbora Strycova, winning 6-3, 6-4 in just over 90 minutes on the hard courts of the Japanese capital.

Osaka – who extends her current win streak to nine matches  – was better in the big moments against the eighth seed, converting all three of her breakpoints.

The pair swapped breaks in the opening set then Osaka broke again in the crucial eighth game, after which she served out the set.

In the second set, Osaka saved a breakpoint early on then broke the Czech to go 4-2 up, never looking back from there.

The victory earns the 20-year-old a semi-final date with Camila Giorgi, who is having a superlative tournament in her own right. On Thursday, the Italian knocked out top seed Caroline Wozniacki and on Friday was 5-3 up in the opening set against Victoria Azarenka before the Belarusian retired hurt.

Elsewhere, fourth seed Karolina Pliskova survived a second set comeback from Alison Riske and needed three match points to win 6-1, 6-7(5), 7-6(4) in a thrilling encounter.

The Czech will face rising star Donna Vekic, who upset second seed Caroline Garcia of France 6-3, 6-4 earlier in the day.