Hideki Matsuyama became the first rookie to win the JGTO money title after capturing the Casio World Open for his fourth victory on Sunday.
Matsuyama, who has turned heads since turning pro in April and began his U.S. PGA career last month, held on to his overnight lead with four birdies and two bogies to finish at 12-under-par 276 — one stroke ahead of Yuta Ikeda at Kochi Kuroshio Country Club in Kochi Prefecture.
Komei Oda finished three strokes off the pace in third.
The feat couldn't have come at a better place for the 21-year-old university student, who wrapped up the money race with one event to spare.
"To win a championship — and clinch the money title — at a course I practiced at in middle school and high school makes me really happy," Matsuyama said.
"I didn't think I would win as much as I have. Coming in with a chance to seal the top spot, I played my most patient round of the tournament and hung on."
Matsuyama, who picked up a winner's check of ¥40 million, has earned slightly more than ¥201 million this season.
He is only the third player to break the 200 million yen mark following Masashi "Jumbo" Ozaki (1994 and 1996) and Toshimitsu Izawa (2001).