Japan Airlines (JAL) confirmed he used one of its Boeing 787s but declined to disclose further details.
Jiji Press news agency said Tanaka booked out the whole plane - which usually has about 200 seats - for a group of five including his wife. His dog - a brown Toy Poodle - was also aboard, the Sports Nippon said.
Given the state of the Yanks' infield post-A-Rod, it's good for Tanaka to get used to seeing so many empty seats.
[SBS Big League Stew