Tennis: Nishikori at Gerry Weber Open

Tennis: Nishikori at Gerry Weber Open

Kei Nishikori of Japan returns a shot in his match against Matthias Bachinger of Germany at the Gerry Weber Open at Gerry Weber Stadium in Halle, Germany, on June 18, 2018. Nishikori won 6-3, 7-6(3). (Kyodo) ==Kyodo

Tennis: Nishikori at Gerry Weber Open

Tennis: Nishikori at Gerry Weber Open

Kei Nishikori of Japan returns a shot in his match against Matthias Bachinger of Germany at the Gerry Weber Open at Gerry Weber Stadium in Halle, Germany, on June 18, 2018. Nishikori won 6-3, 7-6(3). (Kyodo) ==Kyodo

Tennis: Nishikori

Tennis: Nishikori

Japanese tennis player Kei Nishikori (L) shakes hands with Matthias Bachinger after beating the German contender to advance to the quarterfinals of the ATP Challenger Tour event in Dallas, Texas, on Jan. 31, 2018. (Kyodo) ==Kyodo

Tennis: Nishikori

Tennis: Nishikori

Japanese tennis player Kei Nishikori hits a forehand against Matthias Bachinger of Germany during the second round of an ATP Challenger Tour event in Dallas, Texas, on Jan. 31, 2018. (Kyodo) ==Kyodo

Tennis: Nishikori

Tennis: Nishikori

Japanese tennis player Kei Nishikori pumps his fist after a point against Matthias Bachinger of Germany in the second round of the ATP Challenger Tour event in Dallas, Texas, on Jan. 31, 2018. (Kyodo) ==Kyodo

Tennis: Nishikori at Dallas Challenger event

Tennis: Nishikori at Dallas Challenger event

Former world No. 4 Kei Nishikori hits a backhand to Matthias Bachinger of Germany during the second round of an ATP Challenger Tour event in Dallas, Texas, on Jan. 31, 2018. (Kyodo) ==Kyodo

Tennis: Nishikori at Dallas Challenger event

Tennis: Nishikori at Dallas Challenger event

Former world No. 4 Kei Nishikori hits a forehand to Matthias Bachinger during the second round of an ATP Challenger Tour event in Dallas, Texas, on Jan. 31, 2018. (Kyodo) ==Kyodo