TOKYO, September 28, 2014 (AFP) - Fujita sank six birdies and one bogey on the 7,117-yard Ohtone Country Club course in Ibaraki, northeast of Tokyo, and managed a four-day total of six-under-par 278.
The 45-year-old player soared to the top spot after settling for a 14th place tie on the previous day.
"All day today, I was able to submit satisfying golf. I am extremely happy with the result," he said.
"The fact that I was able to play among Asia's leading players and win the tournament gives me a lot of confidence."
He was followed by Kiradech Aphibarnrat of Thailand, South Korea's S.K. Ho and Jason Knutzon of the United States, who finished with a four-day total of 280.
Asian Tour Order of Merit leader David Lipsky of the United States finished with a four-day total 292, settling for a 56th place tie with two other men.
Final scores (Japanese unless noted):
278 - Hiroyuki Fujita 68-71-73-66
280 - Kiradech Aphibarnrat (THA) 71-72-70-67, Jason Knutzon (USA) 71-71-70-68, S. K. Ho (KOR) 68-70-73-69
281 - Baek Seuk-Hyun (KOR) 70-69-73-69, Lee Kyoung-Hoon (KOR) 72-68-72-69, Yoshitaka Takeya 73-67-70-71, Yoshinobu Tsukada 71-71-68-71
282 - Cameron Smith (AUS) 66-74-72-70, Adam Bland (AUS) 69-68-74-71, Juvic Pagunsan (PHI) 69-72-70-71, Scott Strange (AUS) 70-71-70-71, Shingo Katayama 71-71-69-71, Yusaku Miyazato 71-73-66-72, Kazuhiro Yamashita 72-69-68-73, Liang Wenchong (CHN) 70-69-69-74