KATIE BOULTER maintained her impressive form to reach the Hong Kong Open semi-finals after beating Russia’s Anastasia Zakharova in straight sets.

Boulter edged a hard-fought opening set against an inspired Zakharova before running away with the second set to win 6-4 6-0 and faces China’s sixth seed Yue Yuan in the last four.

The British number one, quoted by the BBC, said: “The first set I think I was on another planet.