Contents BioKei Nishikori Relationship StatusKei Nishikori Wife Mai YamauchiKei Nishikori Ex-girlfriend Honami TsuboiBio Kei Nishikori is a Japanese tennis player. He is the only male Japanese tennis player in history to be ranked inside the top 5 in singles, and first reached his career-high singles ranking of world No. 4 in March 2015. He is currently ranked world No. 40 by the Association of