Defending champion Taylor Fritz said he could not cope with an "incredible" turnaround from world No. 215 Shintaro Mochizuki as he crashed out of the Japan Open in a stunning second-round loss on Thursday.
Top-seeded Fritz, the highest-ranked American in the world at No. 10, lost 0-6, 6-4, 7-6 (7-2) against the Japanese wild card, who went into the tournament without a tour-level win to his name.
Fritz, who has won two titles this season, looked to be cruising into the quarterfinals when he took the first set to love in just 29 minutes.