PARIS (REUTERS) - Czech seventh seed Petra Kvitova powered past unseeded German Laura Siegemund 6-3 6-3 to reach the semi-finals of the French Open on Wednesday (Oct 7).

The 30-year-old, a two-time champion at Wimbledon, reached the last-four stage on the claycourts at Roland Garros for the second time since 2012 and has yet to lose a set at this year's tournament in Paris.

Siegemund, ranked 66th in the world, did not pose a challenge in the opening set but gave a good account of herself in the second despite suffering a lower back problem midway through the set.

Kvitova converted her second match point when her 32-year-old opponent served a double fault and the Czech will meet the winner of the all-American clash between Danielle Collins and Australian Open champion Sofia Kenin for a place in the final.