DALLAS, TX - FEBRUARY 02: Kei Nishikori (JPN) hits a forehand volley during the RBC Tennis Championships of Dallas on February 2, 2018 at the T Bar M Racquet Club in Dallas, Texas. (Photo by George Walker/Icon Sportswire via Getty Images)
DALLAS, TX - FEBRUARY 02: Kei Nishikori (JPN) hits a forehand volley during the RBC Tennis Championships of Dallas on February 2, 2018 at the T Bar M Racquet Club in Dallas, Texas. (Photo by George Walker/Icon Sportswire via Getty Images)