Heather Watson in Japan Open semi but Laura Robson out

Britain's Heather Watson advanced to the semi-finals of the Japan Open in Osaka but British number one Laura Robson lost in a final set tie-break.

World number 71 Watson beat Pauline Parmentier of France, ranked 73, 7-5 6-3 in just under two hours and is now guaranteed to move into the top 60.

The 20-year-old faces Japan's Misaki Doe after she beat seventh seed Chanelle Scheepers 2-6 6-1 6-3.

But eighth seed Robson lost 6-3 3-6 7-6 (7-4) to unseeded Chang Kai-chen.

Watson's match featured 12 breaks of serve in the 21 games, with the Guernsey player recording her fourth late in the first set and three more in the second.

Robson,18, the world number 56, dropped her serve twice as she lost the first set to the world number 134, but the deciding set went with serve all the way, with not even a break point for either player, before Chang claimed the crucial advantage.

In the semi-finals she will play top seed Sam Stosur of Australia, who beat American Jamie Hampton 6-2 6-4.

The 2011 US Open champion broke unseeded Hampton's serve seven times, while never facing a break point herself.