As a high school student, he played as a pitcher for Osaka Toin High School and his fastball was clocked at 94 mph. In 2006, he took part in Japan's National High School Baseball Championship, but he was defeated by his opponent Yuki Saito in his second game. Nakata was a highly hyped prospect out of high school, hitting a total of 87 home runs, a Japanese record. On November 3, 2006, during a prefectural tournament game, the 17-year-old cracked a 550' homer out of the park then over a couple houses before landing across the street. That shattered the old record for the park, 425' by future NPB regular Osamu Hamanaka. The Minnesota Twins, New York Mets and Seattle Mariners all expressed interest, with Seattle offering $2.5 million. Nakata turned all of them down to play in Nippon Pro Baseball.
He was in the first pick by Hokkaido Nippon-Ham Fighters in the 2007 draft. He succeeds the number 6, previously belongs to "Mr. Fighters" Yukio Tanaka. He struggled in his first spring training in 2008, and was sent down to ni-gun for seasoning. He fared well, hitting.255/.339/.464 with 11 HR in 196 AB. He was five homers behind Eastern League leader Yohei Kaneko despite missing the last two months after knee surgery. Nakata starred in the minors in 2009, tying the Eastern League RBI record and setting a new homer record. He made it into 22 official games, debuting on May 23 and singling off Ricky Barrett in his first at-bat in Nippon Pro Baseball. He was 10 for 36 with two doubles, three runs, one RBI, one walk and 15 whiffs for Nippon Ham. Nakata was moved to the outfield in 2010, but once again missed two months due to knee surgery. He hit.233/.291/.395 with 9 HR but 61 strikeouts in 210 at-bats. His first NPB homer came off Yuta Omine on July 20. He got six votes for the 2010 Pacific LeagueRookie of the Year Award, well back of Ryo Sakakibara's 87. He also trailed Keisuke Katto, Masahiko Morifuku and Takashi Ogino. As a regular in 2011, Nakata hit.237/.283/.408 with 32 doubles, 18 home runs and 91 RBI. In a low-offense season, he ranked among the Pacific League leaders in many departments. He was third in RBI, second in doubles, tied for third in homers, tied for 5th in total bases, second in sacrifice flies, third in strikeouts, tied for 6th in double play grounders and 9th in slugging. He is the first Fighters player to hit at least 20 homers over three consecutive seasons since Michihiro Ogasawara. Together with then-rookie pitcher Shohei Ohtani, the duo were dubbed the "O-N tandem of the Heisei Era", referencing Sadaharu Oh and Shigeo Nagashima's "O-N cannon" back in their prime with the Yomiuri Giants. Nakata was named the most valuable player of the 2016 Pacific League Climax Series. He was selected for the.
