In doing so Matsuyama elevated his huge following in Japan and, still only 22, there seems no boundaries as to just how far he might go in terms of becoming one of the greats of Japanese golf.
A winner of the Memorial Tournament on the PGA Tour this season, Matsuyama appears set to become the first Japanese golfer to win a major, having already recorded to tens at both the US Open and Open Championships.
Iwata came from seven shots off the 54 hole lead of Matsuyama with a final round of 63 but the playoff went to Matsuyama.
Matsuyama will move up four places in the World Ranking to 16th, the highest ranking in his career to date.
Jordan Spieth and a resurgent Australian Brendan Jones tied for 3rd one shot behind the playoff with Jones continuing his comeback from surgery twelve months ago with arguably his best finish of the season. He had also finished 3rd at the Fujisankei Classic earlier in the year but this was a much bigger stage and he challenged for much of the week.
Neither Jones nor Spieth who were playing with Matsuyama playing the par five last were able to birdie the final hole while the Japanese star did so to catch Iwata who had finished twenty minutes earlier.
Jones earned nearly A$130,000 for his third place finish and moves to 37th on the money list.
The Japan Tour now plays the Casio World Open ahead of the season ending Golf Nippon Series event.
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