Wawrinka, Nishikori through to Japan Open semis

Switzerland's Stan Wawrinka reacts after defeating Austin Krajicek of the U.S. during their men's singles tennis match at the Japan Open championships in Tokyo October 9, 2015. REUTERS/Thomas Peter

TOKYO (Reuters) - French Open champion Stan Wawrinka sailed into the semi-finals of the Japan Open on Friday with a 6-3 6-4 win over American Austin Krajicek.

Wawrinka, who has already won three titles this year including his second grand slam in Paris, needed just 50 minutes to defeat Krajicek .