ARLINGTON -- Yu Darvish's goal is to be the best pitcher in the world. According to news reports out of Japan, he told the Japanese media that's why he asked the Hokkaido Nippon Ham Fighters to be posted in December so he could pitch in the Major Leagues.

The Rangers won the rights to negotiate with Darvish on Dec. 18. They bid $51.7 million and signed him to a six-year, $60 million contract last week.

"I want to become the kind of pitcher that will make people say, 'Darvish is the No. 1 pitcher in the world,'" Darvish said at a news conference on Tuesday.

According to The Associated Press, over 10,000 fans attended Darvish's news conference at the Sapporo Dome on Tuesday. They heard Darvish say that he was looking for a new challenge after seven seasons with the Fighters.

"I want to feel the thrill of pitching against the world's best hitters," Darvish said, according to the Kyodo News Service. "It was becoming harder to stay motivated in Japan. I used to feel that Japan provided the best environment for me. But I came to believe that I needed to change that environment and move to the Majors. As a baseball player, I wanted to fight real battles."

He also said that he wanted to rise to the challenge of upholding the honor of baseball in Japan, according to the Yomiuri Shimbun.

"Japanese players are not thought of as highly as they used to be," Darvish said. "I didn't like the idea that Japanese baseball was looked down upon in the United States. That was a major factor. I've pitched here practically my entire career and gotten so much support, so it's very difficult to leave Hokkaido.

"Japan is a great fit for me, but I believe I have to move on in a different environment. Going to the States was the best decision."

Darvish, 25, was 18-6 with a 1.44 ERA in 28 games and 232 innings for the Fighters last year. It was his fifth straight season with an ERA under 2.00, and his 276 strikeouts in 2011 were the highest by a Japanese pitcher since Hideo Nomo had that many in 1993.

Over the past five seasons, he is 76-28 with a 1.72 ERA in 1,024 innings. He struck out 1,083 and walked 221 while holding opponents to a .192 batting average. He twice won the Pacific League ERA title and earned the Eiji Sawamura Award in 2007 as the top pitcher in Japan.

Now he has set his sights even higher.

"I want to be the world's No. 1 pitcher," Darvish said. "I want to dominate hitters. That is my job."

Darvish is expected to report to Spring Training with the rest of the Texas pitchers and catchers on Feb. 22, in Surprise, Ariz.