The 34-year-old, who had trailed by two strokes overnight, produced ice-cool composure and superb play over the closing stretch as he fired a flawless seven-under-par 63 at Waialae Country Club in Honolulu.
Six players held at least a share of the lead during a wildly fluctuating final round but Walker made his timely charge with birdies at the 13th, 15th, 16th and 17th to post a 17-under total of 263.
Overnight leader Chris Kirk recovered from a slow start to close with a five-birdie 66 and secure outright second place, finishing a stroke in front of fellow American Jerry Kelly (65), the 2002 champion at Waialae.
- Sports & Recreation
- Waialae Country Club