Frank Lickliter overcame bogeys on two of the last three holes to hold off rookie JJ Henry and claim his first PGA Tour win at the Kemper Open.
With rain disrupting play throughout the tournament, the final round was extended an extra day but it was worth the wait for Lickliter, who finished the last nine holes at even-par to complete a 3-under-par 68 for a 72-hole total of 16-under 268.
In his 168th career start, Lickliter became the fifth first-time winner on the PGA Tour this year and the third straight, joining Byron Nelson Classic champion Robert Damron and Spain's Sergio Garcia, who won The Colonial.
Lickliter, 32, pocketed 630,000 US dollars (£443,000) to climb to eighth on the money list with a career-best £1.085,359. He also earned a two-year exemption on the PGA Tour and an invitation to next month's US Open.
Henry, the first-round leader, played just four holes today but made a critical bogey on 16 when he could have forced a play-off.
The 26-year-old posted a final-round 66 to finish a career-best second at 15-under 269 while World Number Two Phil Mickelson continued his stellar play, recording the only bogey-free final round with a 65 to tie for third at 12-under 272.
The left-hander has finished in the top three in six of his last eight events, but has been unable to come up with a victory.
Spike McRoy and second-round leader Bradley Hughes of Australia also finished four shots back.
Collated scores and totals
(USA unless stated, par 71):
268 F Lickliter 69 65 66 68
269 JJ Henry 65 71 67 66
272 B Hughes 70 63 72 67, S McRoy 71 66 67 68, P Mickelson 68 67 72 65
274 T Herron 69 68 68 69, S Hoch 68 70 66 70, P-U Johansson (Swe) 68 69 66 71
275 C DiMarco 65-70-68-72, D Forsman 68 67 67 73, B Schwarzrock 68 67 71 69
276 R Allenby (Aus) 69 67 67 73, C Riley 67 69 69 71
277 B Watts 72 67 69 69, C Beckman 69 69 69 70, C Howell 71 65 71 70
278 F Funk 71 69 71 67, J Haas 69 67 71 71, F Nobilo (Nzl) 66 72 71 69, C Parry
70 70 71 67, P Tataurangi 68 68 71 71
279 Bob Estes 66 69 73 71, B Glasson 73 68 72 66, M Heinen 72 69 67 71, L
Janzen 71 68 69 71, G Kraft 71 70 69 69, L Porter 66 68 71 74, E Toledo (Mex)
70 71 73 65, K Hosokawa 70 65 73 71, M Gogel 71 70 69 69
280 S Appleby (Aus) 65 71 70 74, B Chamblee 72 69 70 69, S Kendall 69 68 71 72,
S Lowery 68 68 71 73, I Leggatt 71 69 71 69, K Johnson 68 68 71 73
281 T Armour III 71 69 67 74, D Hammond 71 66 73 71, J Julian 69 66 76 70, M
O'Meara 67 73 72 69, B Quigley 69 68 77 67, W Wood 67 70 74 70, B Baird 69 68
72 72, J Brehaut 73 68 68 72
282 M Brooks 69 72 70 71, T Pernice Jr 70 68 70 74, G Nicklaus 69 70 72 71
283 M Bradley 70 71 71 71, P Jordan 71 70 69 73, L Mize 72 69 73 69, C Paulson
71 68 73 71, L Roberts 70 70 70 73, M Hensby 71 68 73 71
284 W Austin 68 73 70 73, B Burns 69 72 69 74, J Carter 71 68 72 73, J Leonard
68 68 78 70
285 T Tolles 68 69 69 79, C Tidland 68 73 70 74
286 B Crenshaw 70 70 74 72
287 S Flesch 68 73 72 74, B Elder 71 66 72 78
289 B Bates 69 71 74 75
293 S Allan 70 71 77 75
Disq: G Chalmers (Aus) 71 66 69