The pair finished 72 holes locked on 12-under-par at the Harbour Town Golf Links in South Carolina, Kodaira after a stunning final round 66 against a battling 71 from Kim.
Breezy conditions made scoring difficult on the already tricky layout and as the leaders struggled Kodaira went out in 3-under and came home in 2-under to set the early target.
Overnight leader Ian Poulter dropped five shots on the back nine to tumble down the leaderboard while playing partners Kim and Luke List also struggled on the inward half.
List had four bogeys against two birdies while Kim gave three back to the scorecard.
Kodaira and Kim both parred the course’s iconic 18th hole twice before play moved to the difficult par-3 17th where Kodaira ended proceedings with a lengthy birdie putt.
Kodaira is little known outside Japan but finished T28 at the Masters last week after playing his way into the world top 50 earlier in the year to earn an invite.
He is a six-time winner in his home country though says he was surprised to have tasted success so soon in the US where he has teed up just five times previously.
“To win this quicky is a big surprise to me,” he said through an interpreter in his post round press conference, where he also confirmed his intention to now join the PGA Tour.
“This is the stage I’ve been dreaming about and to have the opportunity to play four times is a dream come true, so of course I will accept (the invitation to take up membership).”
Kim, the reigning Players champion and one of the most promising young players in the game, will be particularly disappointed to have come up short after some poor putting over the closing stretch.
He gave up almost three strokes to the field on the greens in the final round and missed putts from less than 10 feet at each of the last four holes.
Cameron Smith and Rod Pampling led home the Australian contingent, Smith taking at least some positives form the week after recovering from yesterday’s disastrous back nine with a 2-under 69.
Just 20 players broke 70 in the final round, testament to Smith’s good play, though he will rue three double bogeys in a six hole back nine stretch Saturday which cost him a legitimate chance to contend.
Pampling finished the week with nine consecutive pars in a 1-under 70 to also be 5-under and T32, Aaron Baddeley the only other Australian to play the weekend and finishing T55.
SIGNATURE HOLES - 14TH EAST AT THE GRANGE:
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