Sullivan, who plays out of Ashley Plantation in Daleville, Va., had six birdies and four bogeys over the Crosswater Golf Club course, giving him a 6-under 281 total at Sunriver Resort.
He held off Ryan Benzel, an assistant pro at Seattle Golf Club, and Mike Small, head coach at the University of Illinois. Both finished at 2-under 285.
Butch Sheehan, teaching pro at Mission Hills Country Club in Rancho Mirage, Calif., shot a 1-under 71 in the final round. He tied with Tim Thelen, Director of Instruction at Traditions Gold Club at Texas A&M, for fourth at 1-under 286.
The low 20 scores earned a berth to the 89th PGA Championship at Southern Hills Country Club in Tulsa, Okla., Aug. 6-12.