According to The New York Times' report from a Thursday news conference in Tokyo, the right-hander said the Yankees gave him the "highest evaluation" and he is "going there to win the World Series."
"I can't wait to get to the pitcher's mound at Yankee Stadium," Tanaka told reporters, according to the Times.
Tanaka joked that his knowledge of America and the game here is limited -- he has been to New York once, he said, and only remembers the weather being unfavorable -- but his knack for preparation and competitive attitude are among the qualities that drew teams to him. The Yankees beat out a handful of other clubs -- the D-backs, Cubs, White Sox, Dodgers and Astros reportedly among them -- and signed the 25-year-old to a seven-year, $155 million contract.
According to the Times, that contract is the largest given to a Japanese player, and the fifth-largest deal received by a Major League pitcher.
"I'm just relieved it's done," Tanaka said at his news conference.
Tanaka, who went 24-0 last season with the Rakuten Golden Eagles, reportedly did not seem concerned when answering questions about his heavy pitch counts in Japan, and how that might affect him against big league hitters.
"In Japan, a bad pitch might end in a single, but at the Majors, that could be a home run," Tanaka said, according to the Times. "The hitting power is different. And they're careful with pitch counts [in the U.S.]. It's not like I've never played ball before. I don't want to overthink it."
Joey Nowak is a reporter for MLB.com. Follow him on Twitter at @joeynowak. This story was not subject to the approval of Major League Baseball or its clubs.