Bae, whose PGA Tour career was interrupted in 2015 when he returned to his homeland to complete compulsory military service, claimed the Alberstons Boise Open by a shot.
A two-time winner on the main Tour, Bae returned from his two-year absence in time to play a full schedule in 2017/18 but failed to finish in the top 125 of the FedEx Cup.
That meant a trip back to the four-tournament Web.com Finals Series where he finished T35 and T6 in the first two events ahead of his 19-under-par winning performance at this week's penultimate event.
Starting the day with a share of the lead, Bae signed for a 5-under 66 Sunday to edge Americans Anders Albertson and Adam Schenck and Canada’s Roger Sloan by a stroke.
The win now has him in top spot on the money list and if he can maintain that after next week’s Web.com Tour Championship will have unfettered access on the PGA Tour next season.
Aaron Baddeley was the best of the Australians sharing 17th place eight shots back but it is Inverell’s Brett Drewitt who will feel he let an opportunity slip.
After heading to Sunday inside the top 10, Drewitt endured a horror day at the Hillcrest Country Club and an eventual 3-over 74 saw him slip back to T43.
World-class player.September 16, 2018
Having held a share of the lead at the halfway mark, Drewitt was projected inside the top 10 on the four-tournament money list which will award cards to the top 25 earners.
But his disappointing Sunday effort now sees him in need of something special at the final event of the season next week if he is to play the PGA Tour for a second time.
Drewitt played the main circuit in 2017 but finished outside the top 125 and after a third season on the secondary circuit in 2018 was 65th on the regular season money list.
With three of the four events now complete he will need something special in the final tournament in Florida next week as he sits 64th in the end of season earnings.
Baddeley improved three positions on the money list with his good play and at 20th heading to the final tournament is in good position to play the main Tour again in 2019.
Curtis Luck should also graduate though he lost ground this week, dropping to 16th on the standings after a T24 result.
Cameron Davis is the only Australian guaranteed to play the main circuit next year though he missed the cut this week and has fallen to seventh on the money list.
Still outside the top 25 and needing to step up in next week’s Web.com Tour Championship are Cameron Percy, Rhein Gibson, Stuart Appleby and John Senden.
Percy was T24 this week to be 44th on the standings, Gibson T43 to be 57th, Senden also T43 to be T77 in money and Appleby T58 to be T87 in earnings.
SIGNATURE HOLES - 7TH AT NEWCASTLE GC, NSW:
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